--- /dev/null
+Content-Type: text/plain; charset="utf-8"
+MIME-Version: 1.0
+Content-Transfer-Encoding: 7bit
+Subject: [v3,2/5] mtd: nand: Qualcomm NAND controller driver
+From: Archit Taneja <architt@codeaurora.org>
+X-Patchwork-Id: 6927101
+Message-Id: <1438578498-32254-3-git-send-email-architt@codeaurora.org>
+To: linux-mtd@lists.infradead.org, dehrenberg@google.com,
+ cernekee@gmail.com, computersforpeace@gmail.com
+Cc: linux-arm-msm@vger.kernel.org, agross@codeaurora.org,
+ sboyd@codeaurora.org, linux-kernel@vger.kernel.org,
+ Archit Taneja <architt@codeaurora.org>
+Date: Mon, 3 Aug 2015 10:38:15 +0530
+
+The Qualcomm NAND controller is found in SoCs like IPQ806x, MSM7xx,
+MDM9x15 series.
+
+It exists as a sub block inside the IPs EBI2 (External Bus Interface 2)
+and QPIC (Qualcomm Parallel Interface Controller). These IPs provide a
+broader interface for external slow peripheral devices such as LCD and
+NAND/NOR flash memory or SRAM like interfaces.
+
+We add support for the NAND controller found within EBI2. For the SoCs
+of our interest, we only use the NAND controller within EBI2. Therefore,
+it's safe for us to assume that the NAND controller is a standalone block
+within the SoC.
+
+The controller supports 512B, 2kB, 4kB and 8kB page 8-bit and 16-bit NAND
+flash devices. It contains a HW ECC block that supports BCH ECC (4, 8 and
+16 bit correction/step) and RS ECC(4 bit correction/step) that covers main
+and spare data. The controller contains an internal 512 byte page buffer
+to which we read/write via DMA. The EBI2 type NAND controller uses ADM DMA
+for register read/write and data transfers. The controller performs page
+reads and writes at a codeword/step level of 512 bytes. It can support up
+to 2 external chips of different configurations.
+
+The driver prepares register read and write configuration descriptors for
+each codeword, followed by data descriptors to read or write data from the
+controller's internal buffer. It uses a single ADM DMA channel that we get
+via dmaengine API. The controller requires 2 ADM CRCIs for command and
+data flow control. These are passed via DT.
+
+The ecc layout used by the controller is syndrome like, but we can't use
+the standard syndrome ecc ops because of several reasons. First, the amount
+of data bytes covered by ecc isn't same in each step. Second, writing to
+free oob space requires us writing to the entire step in which the oob
+lies. This forces us to create our own ecc ops.
+
+One more difference is how the controller accesses the bad block marker.
+The controller ignores reading the marker when ECC is enabled. ECC needs
+to be explicity disabled to read or write to the bad block marker. For
+this reason, we use the newly created flag NAND_BBT_ACCESS_BBM_RAW to
+read the factory provided bad block markers.
+
+v3:
+- Refactor dma functions for maximum reuse
+- Use dma_slave_confing on stack
+- optimize and clean upempty_page_fixup using memchr_inv
+- ensure portability with dma register reads using le32_* funcs
+- use NAND_USE_BOUNCE_BUFFER instead of doing it ourselves
+- fix handling of return values of dmaengine funcs
+- constify wherever possible
+- Remove dependency on ADM DMA in Kconfig
+- Misc fixes and clean ups
+
+v2:
+- Use new BBT flag that allows us to read BBM in raw mode
+- reduce memcpy-s in the driver
+- some refactor and clean ups because of above changes
+
+Reviewed-by: Andy Gross <agross@codeaurora.org>
+Signed-off-by: Archit Taneja <architt@codeaurora.org>
+
+---
+drivers/mtd/nand/Kconfig | 7 +
+ drivers/mtd/nand/Makefile | 1 +
+ drivers/mtd/nand/qcom_nandc.c | 1913 +++++++++++++++++++++++++++++++++++++++++
+ 3 files changed, 1921 insertions(+)
+ create mode 100644 drivers/mtd/nand/qcom_nandc.c
+
+--- a/drivers/mtd/nand/Kconfig
++++ b/drivers/mtd/nand/Kconfig
+@@ -516,4 +516,11 @@ config MTD_NAND_XWAY
+ Enables support for NAND Flash chips on Lantiq XWAY SoCs. NAND is attached
+ to the External Bus Unit (EBU).
+
++config MTD_NAND_QCOM
++ tristate "Support for NAND on QCOM SoCs"
++ depends on ARCH_QCOM
++ help
++ Enables support for NAND flash chips on SoCs containing the EBI2 NAND
++ controller. This controller is found on IPQ806x SoC.
++
+ endif # MTD_NAND
+--- /dev/null
++++ b/drivers/mtd/nand/qcom_nandc.c
+@@ -0,0 +1,1918 @@
++/*
++ * Copyright (c) 2015, The Linux Foundation. All rights reserved.
++ *
++ * This software is licensed under the terms of the GNU General Public
++ * License version 2, as published by the Free Software Foundation, and
++ * may be copied, distributed, and modified under those terms.
++ *
++ * This program is distributed in the hope that it will be useful,
++ * but WITHOUT ANY WARRANTY; without even the implied warranty of
++ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
++ * GNU General Public License for more details.
++ */
++
++#include <linux/clk.h>
++#include <linux/slab.h>
++#include <linux/bitops.h>
++#include <linux/dma-mapping.h>
++#include <linux/dmaengine.h>
++#include <linux/module.h>
++#include <linux/mtd/nand.h>
++#include <linux/mtd/partitions.h>
++#include <linux/of.h>
++#include <linux/of_device.h>
++#include <linux/of_mtd.h>
++#include <linux/delay.h>
++
++/* NANDc reg offsets */
++#define NAND_FLASH_CMD 0x00
++#define NAND_ADDR0 0x04
++#define NAND_ADDR1 0x08
++#define NAND_FLASH_CHIP_SELECT 0x0c
++#define NAND_EXEC_CMD 0x10
++#define NAND_FLASH_STATUS 0x14
++#define NAND_BUFFER_STATUS 0x18
++#define NAND_DEV0_CFG0 0x20
++#define NAND_DEV0_CFG1 0x24
++#define NAND_DEV0_ECC_CFG 0x28
++#define NAND_DEV1_ECC_CFG 0x2c
++#define NAND_DEV1_CFG0 0x30
++#define NAND_DEV1_CFG1 0x34
++#define NAND_READ_ID 0x40
++#define NAND_READ_STATUS 0x44
++#define NAND_DEV_CMD0 0xa0
++#define NAND_DEV_CMD1 0xa4
++#define NAND_DEV_CMD2 0xa8
++#define NAND_DEV_CMD_VLD 0xac
++#define SFLASHC_BURST_CFG 0xe0
++#define NAND_ERASED_CW_DETECT_CFG 0xe8
++#define NAND_ERASED_CW_DETECT_STATUS 0xec
++#define NAND_EBI2_ECC_BUF_CFG 0xf0
++#define FLASH_BUF_ACC 0x100
++
++#define NAND_CTRL 0xf00
++#define NAND_VERSION 0xf08
++#define NAND_READ_LOCATION_0 0xf20
++#define NAND_READ_LOCATION_1 0xf24
++
++/* dummy register offsets, used by write_reg_dma */
++#define NAND_DEV_CMD1_RESTORE 0xdead
++#define NAND_DEV_CMD_VLD_RESTORE 0xbeef
++
++/* NAND_FLASH_CMD bits */
++#define PAGE_ACC BIT(4)
++#define LAST_PAGE BIT(5)
++
++/* NAND_FLASH_CHIP_SELECT bits */
++#define NAND_DEV_SEL 0
++#define DM_EN BIT(2)
++
++/* NAND_FLASH_STATUS bits */
++#define FS_OP_ERR BIT(4)
++#define FS_READY_BSY_N BIT(5)
++#define FS_MPU_ERR BIT(8)
++#define FS_DEVICE_STS_ERR BIT(16)
++#define FS_DEVICE_WP BIT(23)
++
++/* NAND_BUFFER_STATUS bits */
++#define BS_UNCORRECTABLE_BIT BIT(8)
++#define BS_CORRECTABLE_ERR_MSK 0x1f
++
++/* NAND_DEVn_CFG0 bits */
++#define DISABLE_STATUS_AFTER_WRITE 4
++#define CW_PER_PAGE 6
++#define UD_SIZE_BYTES 9
++#define ECC_PARITY_SIZE_BYTES_RS 19
++#define SPARE_SIZE_BYTES 23
++#define NUM_ADDR_CYCLES 27
++#define STATUS_BFR_READ 30
++#define SET_RD_MODE_AFTER_STATUS 31
++
++/* NAND_DEVn_CFG0 bits */
++#define DEV0_CFG1_ECC_DISABLE 0
++#define WIDE_FLASH 1
++#define NAND_RECOVERY_CYCLES 2
++#define CS_ACTIVE_BSY 5
++#define BAD_BLOCK_BYTE_NUM 6
++#define BAD_BLOCK_IN_SPARE_AREA 16
++#define WR_RD_BSY_GAP 17
++#define ENABLE_BCH_ECC 27
++
++/* NAND_DEV0_ECC_CFG bits */
++#define ECC_CFG_ECC_DISABLE 0
++#define ECC_SW_RESET 1
++#define ECC_MODE 4
++#define ECC_PARITY_SIZE_BYTES_BCH 8
++#define ECC_NUM_DATA_BYTES 16
++#define ECC_FORCE_CLK_OPEN 30
++
++/* NAND_DEV_CMD1 bits */
++#define READ_ADDR 0
++
++/* NAND_DEV_CMD_VLD bits */
++#define READ_START_VLD 0
++
++/* NAND_EBI2_ECC_BUF_CFG bits */
++#define NUM_STEPS 0
++
++/* NAND_ERASED_CW_DETECT_CFG bits */
++#define ERASED_CW_ECC_MASK 1
++#define AUTO_DETECT_RES 0
++#define MASK_ECC (1 << ERASED_CW_ECC_MASK)
++#define RESET_ERASED_DET (1 << AUTO_DETECT_RES)
++#define ACTIVE_ERASED_DET (0 << AUTO_DETECT_RES)
++#define CLR_ERASED_PAGE_DET (RESET_ERASED_DET | MASK_ECC)
++#define SET_ERASED_PAGE_DET (ACTIVE_ERASED_DET | MASK_ECC)
++
++/* NAND_ERASED_CW_DETECT_STATUS bits */
++#define PAGE_ALL_ERASED BIT(7)
++#define CODEWORD_ALL_ERASED BIT(6)
++#define PAGE_ERASED BIT(5)
++#define CODEWORD_ERASED BIT(4)
++#define ERASED_PAGE (PAGE_ALL_ERASED | PAGE_ERASED)
++#define ERASED_CW (CODEWORD_ALL_ERASED | CODEWORD_ERASED)
++
++/* Version Mask */
++#define NAND_VERSION_MAJOR_MASK 0xf0000000
++#define NAND_VERSION_MAJOR_SHIFT 28
++#define NAND_VERSION_MINOR_MASK 0x0fff0000
++#define NAND_VERSION_MINOR_SHIFT 16
++
++/* NAND OP_CMDs */
++#define PAGE_READ 0x2
++#define PAGE_READ_WITH_ECC 0x3
++#define PAGE_READ_WITH_ECC_SPARE 0x4
++#define PROGRAM_PAGE 0x6
++#define PAGE_PROGRAM_WITH_ECC 0x7
++#define PROGRAM_PAGE_SPARE 0x9
++#define BLOCK_ERASE 0xa
++#define FETCH_ID 0xb
++#define RESET_DEVICE 0xd
++
++/*
++ * the NAND controller performs reads/writes with ECC in 516 byte chunks.
++ * the driver calls the chunks 'step' or 'codeword' interchangeably
++ */
++#define NANDC_STEP_SIZE 512
++
++/*
++ * the largest page size we support is 8K, this will have 16 steps/codewords
++ * of 512 bytes each
++ */
++#define MAX_NUM_STEPS (SZ_8K / NANDC_STEP_SIZE)
++
++/* we read at most 3 registers per codeword scan */
++#define MAX_REG_RD (3 * MAX_NUM_STEPS)
++
++/* ECC modes */
++#define ECC_NONE BIT(0)
++#define ECC_RS_4BIT BIT(1)
++#define ECC_BCH_4BIT BIT(2)
++#define ECC_BCH_8BIT BIT(3)
++
++struct desc_info {
++ struct list_head list;
++
++ enum dma_transfer_direction dir;
++ struct scatterlist sgl;
++ struct dma_async_tx_descriptor *dma_desc;
++};
++
++/*
++ * holds the current register values that we want to write. acts as a contiguous
++ * chunk of memory which we use to write the controller registers through DMA.
++ */
++struct nandc_regs {
++ u32 cmd;
++ u32 addr0;
++ u32 addr1;
++ u32 chip_sel;
++ u32 exec;
++
++ u32 cfg0;
++ u32 cfg1;
++ u32 ecc_bch_cfg;
++
++ u32 clrflashstatus;
++ u32 clrreadstatus;
++
++ u32 cmd1;
++ u32 vld;
++
++ u32 orig_cmd1;
++ u32 orig_vld;
++
++ u32 ecc_buf_cfg;
++};
++
++/*
++ * @cmd_crci: ADM DMA CRCI for command flow control
++ * @data_crci: ADM DMA CRCI for data flow control
++ * @list: DMA descriptor list (list of desc_infos)
++ * @dma_done: completion param to denote end of last
++ * descriptor in the list
++ * @data_buffer: our local DMA buffer for page read/writes,
++ * used when we can't use the buffer provided
++ * by upper layers directly
++ * @buf_size/count/start: markers for chip->read_buf/write_buf functions
++ * @reg_read_buf: buffer for reading register data via DMA
++ * @reg_read_pos: marker for data read in reg_read_buf
++ * @cfg0, cfg1, cfg0_raw..: NANDc register configurations needed for
++ * ecc/non-ecc mode for the current nand flash
++ * device
++ * @regs: a contiguous chunk of memory for DMA register
++ * writes
++ * @ecc_strength: 4 bit or 8 bit ecc, received via DT
++ * @bus_width: 8 bit or 16 bit NAND bus width, received via DT
++ * @ecc_modes: supported ECC modes by the current controller,
++ * initialized via DT match data
++ * @cw_size: the number of bytes in a single step/codeword
++ * of a page, consisting of all data, ecc, spare
++ * and reserved bytes
++ * @cw_data: the number of bytes within a codeword protected
++ * by ECC
++ * @bch_enabled: flag to tell whether BCH or RS ECC mode is used
++ * @status: value to be returned if NAND_CMD_STATUS command
++ * is executed
++ */
++struct qcom_nandc_data {
++ struct platform_device *pdev;
++ struct device *dev;
++
++ void __iomem *base;
++ struct resource *res;
++
++ struct clk *core_clk;
++ struct clk *aon_clk;
++
++ /* DMA stuff */
++ struct dma_chan *chan;
++ struct dma_slave_config slave_conf;
++ unsigned int cmd_crci;
++ unsigned int data_crci;
++ struct list_head list;
++ struct completion dma_done;
++
++ /* MTD stuff */
++ struct nand_chip chip;
++ struct mtd_info mtd;
++
++ /* local data buffer and markers */
++ u8 *data_buffer;
++ int buf_size;
++ int buf_count;
++ int buf_start;
++
++ /* local buffer to read back registers */
++ u32 *reg_read_buf;
++ int reg_read_pos;
++
++ /* required configs */
++ u32 cfg0, cfg1;
++ u32 cfg0_raw, cfg1_raw;
++ u32 ecc_buf_cfg;
++ u32 ecc_bch_cfg;
++ u32 clrflashstatus;
++ u32 clrreadstatus;
++ u32 sflashc_burst_cfg;
++ u32 cmd1, vld;
++
++ /* register state */
++ struct nandc_regs *regs;
++
++ /* things we get from DT */
++ int ecc_strength;
++ int bus_width;
++
++ u32 ecc_modes;
++
++ /* misc params */
++ int cw_size;
++ int cw_data;
++ bool use_ecc;
++ bool bch_enabled;
++ u8 status;
++ int last_command;
++};
++
++static inline u32 nandc_read(struct qcom_nandc_data *this, int offset)
++{
++ return ioread32(this->base + offset);
++}
++
++static inline void nandc_write(struct qcom_nandc_data *this, int offset,
++ u32 val)
++{
++ iowrite32(val, this->base + offset);
++}
++
++/* helper to configure address register values */
++static void set_address(struct qcom_nandc_data *this, u16 column, int page)
++{
++ struct nand_chip *chip = &this->chip;
++ struct nandc_regs *regs = this->regs;
++
++ if (chip->options & NAND_BUSWIDTH_16)
++ column >>= 1;
++
++ regs->addr0 = page << 16 | column;
++ regs->addr1 = page >> 16 & 0xff;
++}
++
++/*
++ * update_rw_regs: set up read/write register values, these will be
++ * written to the NAND controller registers via DMA
++ *
++ * @num_cw: number of steps for the read/write operation
++ * @read: read or write operation
++ */
++static void update_rw_regs(struct qcom_nandc_data *this, int num_cw, bool read)
++{
++ struct nandc_regs *regs = this->regs;
++
++ if (read) {
++ if (this->use_ecc)
++ regs->cmd = PAGE_READ_WITH_ECC | PAGE_ACC | LAST_PAGE;
++ else
++ regs->cmd = PAGE_READ | PAGE_ACC | LAST_PAGE;
++ } else {
++ regs->cmd = PROGRAM_PAGE | PAGE_ACC | LAST_PAGE;
++ }
++
++ if (this->use_ecc) {
++ regs->cfg0 = (this->cfg0 & ~(7U << CW_PER_PAGE)) |
++ (num_cw - 1) << CW_PER_PAGE;
++
++ regs->cfg1 = this->cfg1;
++ regs->ecc_bch_cfg = this->ecc_bch_cfg;
++ } else {
++ regs->cfg0 = (this->cfg0_raw & ~(7U << CW_PER_PAGE)) |
++ (num_cw - 1) << CW_PER_PAGE;
++
++ regs->cfg1 = this->cfg1_raw;
++ regs->ecc_bch_cfg = 1 << ECC_CFG_ECC_DISABLE;
++ }
++
++ regs->ecc_buf_cfg = this->ecc_buf_cfg;
++ regs->clrflashstatus = this->clrflashstatus;
++ regs->clrreadstatus = this->clrreadstatus;
++ regs->exec = 1;
++}
++
++static int prep_dma_desc(struct qcom_nandc_data *this, bool read, int reg_off,
++ const void *vaddr, int size, bool flow_control)
++{
++ struct desc_info *desc;
++ struct dma_async_tx_descriptor *dma_desc;
++ struct scatterlist *sgl;
++ struct dma_slave_config slave_conf;
++ int r;
++
++ desc = kzalloc(sizeof(*desc), GFP_KERNEL);
++ if (!desc)
++ return -ENOMEM;
++
++ list_add_tail(&desc->list, &this->list);
++
++ sgl = &desc->sgl;
++
++ sg_init_one(sgl, vaddr, size);
++
++ desc->dir = read ? DMA_DEV_TO_MEM : DMA_MEM_TO_DEV;
++
++ r = dma_map_sg(this->dev, sgl, 1, desc->dir);
++ if (r == 0) {
++ r = -ENOMEM;
++ goto err;
++ }
++
++ memset(&slave_conf, 0x00, sizeof(slave_conf));
++
++ slave_conf.device_fc = flow_control;
++ if (read) {
++ slave_conf.src_maxburst = 16;
++ slave_conf.src_addr = this->res->start + reg_off;
++ slave_conf.slave_id = this->data_crci;
++ } else {
++ slave_conf.dst_maxburst = 16;
++ slave_conf.dst_addr = this->res->start + reg_off;
++ slave_conf.slave_id = this->cmd_crci;
++ }
++
++ r = dmaengine_slave_config(this->chan, &slave_conf);
++ if (r) {
++ dev_err(this->dev, "failed to configure dma channel\n");
++ goto err;
++ }
++
++ dma_desc = dmaengine_prep_slave_sg(this->chan, sgl, 1, desc->dir, 0);
++ if (!dma_desc) {
++ dev_err(this->dev, "failed to prepare desc\n");
++ r = -EINVAL;
++ goto err;
++ }
++
++ desc->dma_desc = dma_desc;
++
++ return 0;
++err:
++ kfree(desc);
++
++ return r;
++}
++
++/*
++ * read_reg_dma: prepares a descriptor to read a given number of
++ * contiguous registers to the reg_read_buf pointer
++ *
++ * @first: offset of the first register in the contiguous block
++ * @num_regs: number of registers to read
++ */
++static int read_reg_dma(struct qcom_nandc_data *this, int first, int num_regs)
++{
++ bool flow_control = false;
++ void *vaddr;
++ int size;
++
++ if (first == NAND_READ_ID || first == NAND_FLASH_STATUS)
++ flow_control = true;
++
++ size = num_regs * sizeof(u32);
++ vaddr = this->reg_read_buf + this->reg_read_pos;
++ this->reg_read_pos += num_regs;
++
++ return prep_dma_desc(this, true, first, vaddr, size, flow_control);
++}
++
++/*
++ * write_reg_dma: prepares a descriptor to write a given number of
++ * contiguous registers
++ *
++ * @first: offset of the first register in the contiguous block
++ * @num_regs: number of registers to write
++ */
++static int write_reg_dma(struct qcom_nandc_data *this, int first, int num_regs)
++{
++ bool flow_control = false;
++ struct nandc_regs *regs = this->regs;
++ void *vaddr;
++ int size;
++
++ switch (first) {
++ case NAND_FLASH_CMD:
++ vaddr = ®s->cmd;
++ flow_control = true;
++ break;
++ case NAND_EXEC_CMD:
++ vaddr = ®s->exec;
++ break;
++ case NAND_FLASH_STATUS:
++ vaddr = ®s->clrflashstatus;
++ break;
++ case NAND_DEV0_CFG0:
++ vaddr = ®s->cfg0;
++ break;
++ case NAND_READ_STATUS:
++ vaddr = ®s->clrreadstatus;
++ break;
++ case NAND_DEV_CMD1:
++ vaddr = ®s->cmd1;
++ break;
++ case NAND_DEV_CMD1_RESTORE:
++ first = NAND_DEV_CMD1;
++ vaddr = ®s->orig_cmd1;
++ break;
++ case NAND_DEV_CMD_VLD:
++ vaddr = ®s->vld;
++ break;
++ case NAND_DEV_CMD_VLD_RESTORE:
++ first = NAND_DEV_CMD_VLD;
++ vaddr = ®s->orig_vld;
++ break;
++ case NAND_EBI2_ECC_BUF_CFG:
++ vaddr = ®s->ecc_buf_cfg;
++ break;
++ default:
++ dev_err(this->dev, "invalid starting register\n");
++ return -EINVAL;
++ }
++
++ size = num_regs * sizeof(u32);
++
++ return prep_dma_desc(this, false, first, vaddr, size, flow_control);
++}
++
++/*
++ * read_data_dma: prepares a DMA descriptor to transfer data from the
++ * controller's internal buffer to the buffer 'vaddr'
++ *
++ * @reg_off: offset within the controller's data buffer
++ * @vaddr: virtual address of the buffer we want to write to
++ * @size: DMA transaction size in bytes
++ */
++static int read_data_dma(struct qcom_nandc_data *this, int reg_off,
++ const u8 *vaddr, int size)
++{
++ return prep_dma_desc(this, true, reg_off, vaddr, size, false);
++}
++
++/*
++ * write_data_dma: prepares a DMA descriptor to transfer data from
++ * 'vaddr' to the controller's internal buffer
++ *
++ * @reg_off: offset within the controller's data buffer
++ * @vaddr: virtual address of the buffer we want to read from
++ * @size: DMA transaction size in bytes
++ */
++static int write_data_dma(struct qcom_nandc_data *this, int reg_off,
++ const u8 *vaddr, int size)
++{
++ return prep_dma_desc(this, false, reg_off, vaddr, size, false);
++}
++
++/*
++ * helper to prepare dma descriptors to configure registers needed for reading a
++ * codeword/step in a page
++ */
++static void config_cw_read(struct qcom_nandc_data *this)
++{
++ write_reg_dma(this, NAND_FLASH_CMD, 3);
++ write_reg_dma(this, NAND_DEV0_CFG0, 3);
++ write_reg_dma(this, NAND_EBI2_ECC_BUF_CFG, 1);
++
++ write_reg_dma(this, NAND_EXEC_CMD, 1);
++
++ read_reg_dma(this, NAND_FLASH_STATUS, 2);
++ read_reg_dma(this, NAND_ERASED_CW_DETECT_STATUS, 1);
++}
++
++/*
++ * helpers to prepare dma descriptors used to configure registers needed for
++ * writing a codeword/step in a page
++ */
++static void config_cw_write_pre(struct qcom_nandc_data *this)
++{
++ write_reg_dma(this, NAND_FLASH_CMD, 3);
++ write_reg_dma(this, NAND_DEV0_CFG0, 3);
++ write_reg_dma(this, NAND_EBI2_ECC_BUF_CFG, 1);
++}
++
++static void config_cw_write_post(struct qcom_nandc_data *this)
++{
++ write_reg_dma(this, NAND_EXEC_CMD, 1);
++
++ read_reg_dma(this, NAND_FLASH_STATUS, 1);
++
++ write_reg_dma(this, NAND_FLASH_STATUS, 1);
++ write_reg_dma(this, NAND_READ_STATUS, 1);
++}
++
++/*
++ * the following functions are used within chip->cmdfunc() to perform different
++ * NAND_CMD_* commands
++ */
++
++/* sets up descriptors for NAND_CMD_PARAM */
++static int nandc_param(struct qcom_nandc_data *this)
++{
++ struct nandc_regs *regs = this->regs;
++
++ /*
++ * NAND_CMD_PARAM is called before we know much about the FLASH chip
++ * in use. we configure the controller to perform a raw read of 512
++ * bytes to read onfi params
++ */
++ regs->cmd = PAGE_READ | PAGE_ACC | LAST_PAGE;
++ regs->addr0 = 0;
++ regs->addr1 = 0;
++ regs->cfg0 = 0 << CW_PER_PAGE
++ | 512 << UD_SIZE_BYTES
++ | 5 << NUM_ADDR_CYCLES
++ | 0 << SPARE_SIZE_BYTES;
++
++ regs->cfg1 = 7 << NAND_RECOVERY_CYCLES
++ | 0 << CS_ACTIVE_BSY
++ | 17 << BAD_BLOCK_BYTE_NUM
++ | 1 << BAD_BLOCK_IN_SPARE_AREA
++ | 2 << WR_RD_BSY_GAP
++ | 0 << WIDE_FLASH
++ | 1 << DEV0_CFG1_ECC_DISABLE;
++
++ regs->ecc_bch_cfg = 1 << ECC_CFG_ECC_DISABLE;
++
++ /* configure CMD1 and VLD for ONFI param probing */
++ regs->vld = (this->vld & ~(1 << READ_START_VLD))
++ | 0 << READ_START_VLD;
++
++ regs->cmd1 = (this->cmd1 & ~(0xFF << READ_ADDR))
++ | NAND_CMD_PARAM << READ_ADDR;
++
++ regs->exec = 1;
++
++ regs->orig_cmd1 = this->cmd1;
++ regs->orig_vld = this->vld;
++
++ write_reg_dma(this, NAND_DEV_CMD_VLD, 1);
++ write_reg_dma(this, NAND_DEV_CMD1, 1);
++
++ this->buf_count = 512;
++ memset(this->data_buffer, 0xff, this->buf_count);
++
++ config_cw_read(this);
++
++ read_data_dma(this, FLASH_BUF_ACC, this->data_buffer, this->buf_count);
++
++ /* restore CMD1 and VLD regs */
++ write_reg_dma(this, NAND_DEV_CMD1_RESTORE, 1);
++ write_reg_dma(this, NAND_DEV_CMD_VLD_RESTORE, 1);
++
++ return 0;
++}
++
++/* sets up descriptors for NAND_CMD_ERASE1 */
++static int erase_block(struct qcom_nandc_data *this, int page_addr)
++{
++ struct nandc_regs *regs = this->regs;
++
++ regs->cmd = BLOCK_ERASE | PAGE_ACC | LAST_PAGE;
++ regs->addr0 = page_addr;
++ regs->addr1 = 0;
++ regs->cfg0 = this->cfg0_raw & ~(7 << CW_PER_PAGE);
++ regs->cfg1 = this->cfg1_raw;
++ regs->exec = 1;
++ regs->clrflashstatus = this->clrflashstatus;
++ regs->clrreadstatus = this->clrreadstatus;
++
++ write_reg_dma(this, NAND_FLASH_CMD, 3);
++ write_reg_dma(this, NAND_DEV0_CFG0, 2);
++ write_reg_dma(this, NAND_EXEC_CMD, 1);
++
++ read_reg_dma(this, NAND_FLASH_STATUS, 1);
++
++ write_reg_dma(this, NAND_FLASH_STATUS, 1);
++ write_reg_dma(this, NAND_READ_STATUS, 1);
++
++ return 0;
++}
++
++/* sets up descriptors for NAND_CMD_READID */
++static int read_id(struct qcom_nandc_data *this, int column)
++{
++ struct nandc_regs *regs = this->regs;
++
++ if (column == -1)
++ return 0;
++
++ regs->cmd = FETCH_ID;
++ regs->addr0 = column;
++ regs->addr1 = 0;
++ regs->chip_sel = DM_EN;
++ regs->exec = 1;
++
++ write_reg_dma(this, NAND_FLASH_CMD, 4);
++ write_reg_dma(this, NAND_EXEC_CMD, 1);
++
++ read_reg_dma(this, NAND_READ_ID, 1);
++
++ return 0;
++}
++
++/* sets up descriptors for NAND_CMD_RESET */
++static int reset(struct qcom_nandc_data *this)
++{
++ struct nandc_regs *regs = this->regs;
++
++ regs->cmd = RESET_DEVICE;
++ regs->exec = 1;
++
++ write_reg_dma(this, NAND_FLASH_CMD, 1);
++ write_reg_dma(this, NAND_EXEC_CMD, 1);
++
++ read_reg_dma(this, NAND_FLASH_STATUS, 1);
++
++ return 0;
++}
++
++/* helpers to submit/free our list of dma descriptors */
++static void dma_callback(void *param)
++{
++ struct qcom_nandc_data *this = param;
++ struct completion *c = &this->dma_done;
++
++ complete(c);
++}
++
++static int submit_descs(struct qcom_nandc_data *this)
++{
++ struct completion *c = &this->dma_done;
++ struct desc_info *desc;
++ int r;
++
++ init_completion(c);
++
++ list_for_each_entry(desc, &this->list, list) {
++ /*
++ * we add a callback to the last descriptor in our list to
++ * notify completion of command
++ */
++ if (list_is_last(&desc->list, &this->list)) {
++ desc->dma_desc->callback = dma_callback;
++ desc->dma_desc->callback_param = this;
++ }
++
++ dmaengine_submit(desc->dma_desc);
++ }
++
++ dma_async_issue_pending(this->chan);
++
++ r = wait_for_completion_timeout(c, msecs_to_jiffies(500));
++ if (!r)
++ return -ETIMEDOUT;
++
++ return 0;
++}
++
++static void free_descs(struct qcom_nandc_data *this)
++{
++ struct desc_info *desc, *n;
++
++ list_for_each_entry_safe(desc, n, &this->list, list) {
++ list_del(&desc->list);
++ dma_unmap_sg(this->dev, &desc->sgl, 1, desc->dir);
++ kfree(desc);
++ }
++}
++
++/* reset the register read buffer for next NAND operation */
++static void clear_read_regs(struct qcom_nandc_data *this)
++{
++ this->reg_read_pos = 0;
++ memset(this->reg_read_buf, 0, MAX_REG_RD * sizeof(*this->reg_read_buf));
++}
++
++static void pre_command(struct qcom_nandc_data *this, int command)
++{
++ this->buf_count = 0;
++ this->buf_start = 0;
++ this->use_ecc = false;
++ this->last_command = command;
++
++ clear_read_regs(this);
++}
++
++/*
++ * this is called after NAND_CMD_PAGEPROG and NAND_CMD_ERASE1 to set our
++ * privately maintained status byte, this status byte can be read after
++ * NAND_CMD_STATUS is called
++ */
++static void parse_erase_write_errors(struct qcom_nandc_data *this, int command)
++{
++ struct nand_chip *chip = &this->chip;
++ struct nand_ecc_ctrl *ecc = &chip->ecc;
++ int num_cw;
++ int i;
++
++ num_cw = command == NAND_CMD_PAGEPROG ? ecc->steps : 1;
++
++ for (i = 0; i < num_cw; i++) {
++ __le32 flash_status = le32_to_cpu(this->reg_read_buf[i]);
++
++ if (flash_status & FS_MPU_ERR)
++ this->status &= ~NAND_STATUS_WP;
++
++ if (flash_status & FS_OP_ERR || (i == (num_cw - 1) &&
++ (flash_status & FS_DEVICE_STS_ERR)))
++ this->status |= NAND_STATUS_FAIL;
++ }
++}
++
++static void post_command(struct qcom_nandc_data *this, int command)
++{
++ switch (command) {
++ case NAND_CMD_READID:
++ memcpy(this->data_buffer, this->reg_read_buf, this->buf_count);
++ break;
++ case NAND_CMD_PAGEPROG:
++ case NAND_CMD_ERASE1:
++ parse_erase_write_errors(this, command);
++ break;
++ default:
++ break;
++ }
++}
++
++/*
++ * Implements chip->cmdfunc. It's only used for a limited set of commands.
++ * The rest of the commands wouldn't be called by upper layers. For example,
++ * NAND_CMD_READOOB would never be called because we have our own versions
++ * of read_oob ops for nand_ecc_ctrl.
++ */
++static void qcom_nandc_command(struct mtd_info *mtd, unsigned int command,
++ int column, int page_addr)
++{
++ struct nand_chip *chip = mtd->priv;
++ struct nand_ecc_ctrl *ecc = &chip->ecc;
++ struct qcom_nandc_data *this = chip->priv;
++ bool wait = false;
++ int r = 0;
++
++ pre_command(this, command);
++
++ switch (command) {
++ case NAND_CMD_RESET:
++ r = reset(this);
++ wait = true;
++ break;
++
++ case NAND_CMD_READID:
++ this->buf_count = 4;
++ r = read_id(this, column);
++ wait = true;
++ break;
++
++ case NAND_CMD_PARAM:
++ r = nandc_param(this);
++ wait = true;
++ break;
++
++ case NAND_CMD_ERASE1:
++ r = erase_block(this, page_addr);
++ wait = true;
++ break;
++
++ case NAND_CMD_READ0:
++ /* we read the entire page for now */
++ WARN_ON(column != 0);
++
++ this->use_ecc = true;
++ set_address(this, 0, page_addr);
++ update_rw_regs(this, ecc->steps, true);
++ break;
++
++ case NAND_CMD_SEQIN:
++ WARN_ON(column != 0);
++ set_address(this, 0, page_addr);
++ break;
++
++ case NAND_CMD_PAGEPROG:
++ case NAND_CMD_STATUS:
++ case NAND_CMD_NONE:
++ default:
++ break;
++ }
++
++ if (r) {
++ dev_err(this->dev, "failure executing command %d\n",
++ command);
++ free_descs(this);
++ return;
++ }
++
++ if (wait) {
++ r = submit_descs(this);
++ if (r)
++ dev_err(this->dev,
++ "failure submitting descs for command %d\n",
++ command);
++ }
++
++ free_descs(this);
++
++ post_command(this, command);
++}
++
++/*
++ * when using RS ECC, the NAND controller flags an error when reading an
++ * erased page. however, there are special characters at certain offsets when
++ * we read the erased page. we check here if the page is really empty. if so,
++ * we replace the magic characters with 0xffs
++ */
++static bool empty_page_fixup(struct qcom_nandc_data *this, u8 *data_buf)
++{
++ struct mtd_info *mtd = &this->mtd;
++ struct nand_chip *chip = &this->chip;
++ struct nand_ecc_ctrl *ecc = &chip->ecc;
++ int cwperpage = ecc->steps;
++ u8 orig1[MAX_NUM_STEPS], orig2[MAX_NUM_STEPS];
++ int i, j;
++
++ /* if BCH is enabled, HW will take care of detecting erased pages */
++ if (this->bch_enabled || !this->use_ecc)
++ return false;
++
++ for (i = 0; i < cwperpage; i++) {
++ u8 *empty1, *empty2;
++ __le32 flash_status = le32_to_cpu(this->reg_read_buf[3 * i]);
++
++ /*
++ * an erased page flags an error in NAND_FLASH_STATUS, check if
++ * the page is erased by looking for 0x54s at offsets 3 and 175
++ * from the beginning of each codeword
++ */
++ if (!(flash_status & FS_OP_ERR))
++ break;
++
++ empty1 = &data_buf[3 + i * this->cw_data];
++ empty2 = &data_buf[175 + i * this->cw_data];
++
++ /*
++ * if the error wasn't because of an erased page, bail out and
++ * and let someone else do the error checking
++ */
++ if ((*empty1 == 0x54 && *empty2 == 0xff) ||
++ (*empty1 == 0xff && *empty2 == 0x54)) {
++ orig1[i] = *empty1;
++ orig2[i] = *empty2;
++
++ *empty1 = 0xff;
++ *empty2 = 0xff;
++ } else {
++ break;
++ }
++ }
++
++ if (i < cwperpage || memchr_inv(data_buf, 0xff, mtd->writesize))
++ goto not_empty;
++
++ /*
++ * tell the caller that the page was empty and is fixed up, so that
++ * parse_read_errors() doesn't think it's an error
++ */
++ return true;
++
++not_empty:
++ /* restore original values if not empty*/
++ for (j = 0; j < i; j++) {
++ data_buf[3 + j * this->cw_data] = orig1[j];
++ data_buf[175 + j * this->cw_data] = orig2[j];
++ }
++
++ return false;
++}
++
++struct read_stats {
++ __le32 flash;
++ __le32 buffer;
++ __le32 erased_cw;
++};
++
++/*
++ * reads back status registers set by the controller to notify page read
++ * errors. this is equivalent to what 'ecc->correct()' would do.
++ */
++static int parse_read_errors(struct qcom_nandc_data *this, bool erased_page)
++{
++ struct mtd_info *mtd = &this->mtd;
++ struct nand_chip *chip = &this->chip;
++ struct nand_ecc_ctrl *ecc = &chip->ecc;
++ int cwperpage = ecc->steps;
++ unsigned int max_bitflips = 0;
++ int i;
++
++ for (i = 0; i < cwperpage; i++) {
++ int stat;
++ struct read_stats *buf;
++
++ buf = (struct read_stats *) (this->reg_read_buf + 3 * i);
++
++ buf->flash = le32_to_cpu(buf->flash);
++ buf->buffer = le32_to_cpu(buf->buffer);
++ buf->erased_cw = le32_to_cpu(buf->erased_cw);
++
++ if (buf->flash & (FS_OP_ERR | FS_MPU_ERR)) {
++
++ /* ignore erased codeword errors */
++ if (this->bch_enabled) {
++ if ((buf->erased_cw & ERASED_CW) == ERASED_CW)
++ continue;
++ } else if (erased_page) {
++ continue;
++ }
++
++ if (buf->buffer & BS_UNCORRECTABLE_BIT) {
++ mtd->ecc_stats.failed++;
++ continue;
++ }
++ }
++
++ stat = buf->buffer & BS_CORRECTABLE_ERR_MSK;
++ mtd->ecc_stats.corrected += stat;
++
++ max_bitflips = max_t(unsigned int, max_bitflips, stat);
++ }
++
++ return max_bitflips;
++}
++
++/*
++ * helper to perform the actual page read operation, used by ecc->read_page()
++ * and ecc->read_oob()
++ */
++static int read_page_low(struct qcom_nandc_data *this, u8 *data_buf,
++ u8 *oob_buf)
++{
++ struct nand_chip *chip = &this->chip;
++ struct nand_ecc_ctrl *ecc = &chip->ecc;
++ int i, r;
++
++ /* queue cmd descs for each codeword */
++ for (i = 0; i < ecc->steps; i++) {
++ int data_size, oob_size;
++
++ if (i == (ecc->steps - 1)) {
++ data_size = ecc->size - ((ecc->steps - 1) << 2);
++ oob_size = (ecc->steps << 2) + ecc->bytes;
++ } else {
++ data_size = this->cw_data;
++ oob_size = ecc->bytes;
++ }
++
++ config_cw_read(this);
++
++ if (data_buf)
++ read_data_dma(this, FLASH_BUF_ACC, data_buf, data_size);
++
++ if (oob_buf)
++ read_data_dma(this, FLASH_BUF_ACC + data_size, oob_buf,
++ oob_size);
++
++ if (data_buf)
++ data_buf += data_size;
++ if (oob_buf)
++ oob_buf += oob_size;
++ }
++
++ r = submit_descs(this);
++ if (r)
++ dev_err(this->dev, "failure to read page/oob\n");
++
++ free_descs(this);
++
++ return r;
++}
++
++/*
++ * a helper that copies the last step/codeword of a page (containing free oob)
++ * into our local buffer
++ */
++static int copy_last_cw(struct qcom_nandc_data *this, bool use_ecc, int page)
++{
++ struct nand_chip *chip = &this->chip;
++ struct nand_ecc_ctrl *ecc = &chip->ecc;
++ int size;
++ int r;
++
++ clear_read_regs(this);
++
++ size = use_ecc ? this->cw_data : this->cw_size;
++
++ /* prepare a clean read buffer */
++ memset(this->data_buffer, 0xff, size);
++
++ this->use_ecc = use_ecc;
++ set_address(this, this->cw_size * (ecc->steps - 1), page);
++ update_rw_regs(this, 1, true);
++
++ config_cw_read(this);
++
++ read_data_dma(this, FLASH_BUF_ACC, this->data_buffer, size);
++
++ r = submit_descs(this);
++ if (r)
++ dev_err(this->dev, "failed to copy last codeword\n");
++
++ free_descs(this);
++
++ return r;
++}
++
++/* implements ecc->read_page() */
++static int qcom_nandc_read_page(struct mtd_info *mtd, struct nand_chip *chip,
++ uint8_t *buf, int oob_required, int page)
++{
++ struct qcom_nandc_data *this = chip->priv;
++ u8 *data_buf, *oob_buf = NULL;
++ bool erased_page;
++ int r;
++
++ data_buf = buf;
++ oob_buf = oob_required ? chip->oob_poi : NULL;
++
++ r = read_page_low(this, data_buf, oob_buf);
++ if (r) {
++ dev_err(this->dev, "failure to read page\n");
++ return r;
++ }
++
++ erased_page = empty_page_fixup(this, data_buf);
++
++ return parse_read_errors(this, erased_page);
++}
++
++/* implements ecc->read_oob() */
++static int qcom_nandc_read_oob(struct mtd_info *mtd, struct nand_chip *chip,
++ int page)
++{
++ struct qcom_nandc_data *this = chip->priv;
++ struct nand_ecc_ctrl *ecc = &chip->ecc;
++ int r;
++
++ clear_read_regs(this);
++
++ this->use_ecc = true;
++ set_address(this, 0, page);
++ update_rw_regs(this, ecc->steps, true);
++
++ r = read_page_low(this, NULL, chip->oob_poi);
++ if (r)
++ dev_err(this->dev, "failure to read oob\n");
++
++ return r;
++}
++
++/* implements ecc->read_oob_raw(), used to read the bad block marker flag */
++static int qcom_nandc_read_oob_raw(struct mtd_info *mtd, struct nand_chip *chip,
++ int page)
++{
++ struct qcom_nandc_data *this = chip->priv;
++ struct nand_ecc_ctrl *ecc = &chip->ecc;
++ uint8_t *oob = chip->oob_poi;
++ int start, length;
++ int r;
++
++ /*
++ * configure registers for a raw page read, the address is set to the
++ * beginning of the last codeword, we don't care about reading ecc
++ * portion of oob, just the free stuff
++ */
++ r = copy_last_cw(this, false, page);
++ if (r)
++ return r;
++
++ /*
++ * reading raw oob has 2 parts, first the bad block byte, then the
++ * actual free oob region. perform a memcpy in two steps
++ */
++ start = mtd->writesize - (this->cw_size * (ecc->steps - 1));
++ length = chip->options & NAND_BUSWIDTH_16 ? 2 : 1;
++
++ memcpy(oob, this->data_buffer + start, length);
++
++ oob += length;
++
++ start = this->cw_data - (ecc->steps << 2) + 1;
++ length = ecc->steps << 2;
++
++ memcpy(oob, this->data_buffer + start, length);
++
++ return 0;
++}
++
++/* implements ecc->write_page() */
++static int qcom_nandc_write_page(struct mtd_info *mtd, struct nand_chip *chip,
++ const uint8_t *buf, int oob_required)
++{
++ struct qcom_nandc_data *this = chip->priv;
++ struct nand_ecc_ctrl *ecc = &chip->ecc;
++ u8 *data_buf, *oob_buf;
++ int i, r = 0;
++
++ clear_read_regs(this);
++
++ data_buf = (u8 *) buf;
++ oob_buf = chip->oob_poi;
++
++ this->use_ecc = true;
++ update_rw_regs(this, ecc->steps, false);
++
++ for (i = 0; i < ecc->steps; i++) {
++ int data_size, oob_size;
++
++ if (i == (ecc->steps - 1)) {
++ data_size = ecc->size - ((ecc->steps - 1) << 2);
++ oob_size = (ecc->steps << 2) + ecc->bytes;
++ } else {
++ data_size = this->cw_data;
++ oob_size = ecc->bytes;
++ }
++
++ config_cw_write_pre(this);
++ write_data_dma(this, FLASH_BUF_ACC, data_buf, data_size);
++
++ /*
++ * we don't really need to write anything to oob for the
++ * first n - 1 codewords since these oob regions just
++ * contain ecc that's written by the controller itself
++ */
++ if (i == (ecc->steps - 1))
++ write_data_dma(this, FLASH_BUF_ACC + data_size,
++ oob_buf, oob_size);
++ config_cw_write_post(this);
++
++ data_buf += data_size;
++ oob_buf += oob_size;
++ }
++
++ r = submit_descs(this);
++ if (r)
++ dev_err(this->dev, "failure to write page\n");
++
++ free_descs(this);
++
++ return r;
++}
++
++/*
++ * implements ecc->write_oob()
++ *
++ * the NAND controller cannot write only data or only oob within a codeword,
++ * since ecc is calculated for the combined codeword. we first copy the
++ * entire contents for the last codeword(data + oob), replace the old oob
++ * with the new one in chip->oob_poi, and then write the entire codeword.
++ * this read-copy-write operation results in a slight perormance loss.
++ */
++static int qcom_nandc_write_oob(struct mtd_info *mtd, struct nand_chip *chip,
++ int page)
++{
++ struct qcom_nandc_data *this = chip->priv;
++ struct nand_ecc_ctrl *ecc = &chip->ecc;
++ uint8_t *oob = chip->oob_poi;
++ int free_boff;
++ int data_size, oob_size;
++ int r, status = 0;
++
++ r = copy_last_cw(this, true, page);
++ if (r)
++ return r;
++
++ clear_read_regs(this);
++
++ /* calculate the data and oob size for the last codeword/step */
++ data_size = ecc->size - ((ecc->steps - 1) << 2);
++ oob_size = (ecc->steps << 2) + ecc->bytes;
++
++ /*
++ * the location of spare data in the oob buffer, we could also use
++ * ecc->layout.oobfree here
++ */
++ free_boff = ecc->bytes * (ecc->steps - 1);
++
++ /* override new oob content to last codeword */
++ memcpy(this->data_buffer + data_size, oob + free_boff, oob_size);
++
++ this->use_ecc = true;
++ set_address(this, this->cw_size * (ecc->steps - 1), page);
++ update_rw_regs(this, 1, false);
++
++ config_cw_write_pre(this);
++ write_data_dma(this, FLASH_BUF_ACC, this->data_buffer,
++ data_size + oob_size);
++ config_cw_write_post(this);
++
++ r = submit_descs(this);
++
++ free_descs(this);
++
++ if (r) {
++ dev_err(this->dev, "failure to write oob\n");
++ return -EIO;
++ }
++
++ chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
++
++ status = chip->waitfunc(mtd, chip);
++
++ return status & NAND_STATUS_FAIL ? -EIO : 0;
++}
++
++/* implements ecc->write_oob_raw(), used to write bad block marker flag */
++static int qcom_nandc_write_oob_raw(struct mtd_info *mtd,
++ struct nand_chip *chip, int page)
++{
++ struct qcom_nandc_data *this = chip->priv;
++ struct nand_ecc_ctrl *ecc = &chip->ecc;
++ uint8_t *oob = chip->oob_poi;
++ int start, length;
++ int r, status = 0;
++
++ r = copy_last_cw(this, false, page);
++ if (r)
++ return r;
++
++ clear_read_regs(this);
++
++ /*
++ * writing raw oob has 2 parts, first the bad block region, then the
++ * actual free region
++ */
++ start = mtd->writesize - (this->cw_size * (ecc->steps - 1));
++ length = chip->options & NAND_BUSWIDTH_16 ? 2 : 1;
++
++ memcpy(this->data_buffer + start, oob, length);
++
++ oob += length;
++
++ start = this->cw_data - (ecc->steps << 2) + 1;
++ length = ecc->steps << 2;
++
++ memcpy(this->data_buffer + start, oob, length);
++
++ /* prepare write */
++ this->use_ecc = false;
++ set_address(this, this->cw_size * (ecc->steps - 1), page);
++ update_rw_regs(this, 1, false);
++
++ config_cw_write_pre(this);
++ write_data_dma(this, FLASH_BUF_ACC, this->data_buffer, this->cw_size);
++ config_cw_write_post(this);
++
++ r = submit_descs(this);
++
++ free_descs(this);
++
++ if (r) {
++ dev_err(this->dev, "failure to write updated oob\n");
++ return -EIO;
++ }
++
++ chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
++
++ status = chip->waitfunc(mtd, chip);
++
++ return status & NAND_STATUS_FAIL ? -EIO : 0;
++}
++
++/*
++ * the three functions below implement chip->read_byte(), chip->read_buf()
++ * and chip->write_buf() respectively. these aren't used for
++ * reading/writing page data, they are used for smaller data like reading
++ * id, status etc
++ */
++static uint8_t qcom_nandc_read_byte(struct mtd_info *mtd)
++{
++ struct nand_chip *chip = mtd->priv;
++ struct qcom_nandc_data *this = chip->priv;
++ uint8_t *buf = this->data_buffer;
++ uint8_t ret = 0x0;
++
++ if (this->last_command == NAND_CMD_STATUS) {
++ ret = this->status;
++
++ this->status = NAND_STATUS_READY | NAND_STATUS_WP;
++
++ return ret;
++ }
++
++ if (this->buf_start < this->buf_count)
++ ret = buf[this->buf_start++];
++
++ return ret;
++}
++
++static void qcom_nandc_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
++{
++ struct nand_chip *chip = mtd->priv;
++ struct qcom_nandc_data *this = chip->priv;
++ int real_len = min_t(size_t, len, this->buf_count - this->buf_start);
++
++ memcpy(buf, this->data_buffer + this->buf_start, real_len);
++ this->buf_start += real_len;
++}
++
++static void qcom_nandc_write_buf(struct mtd_info *mtd, const uint8_t *buf,
++ int len)
++{
++ struct nand_chip *chip = mtd->priv;
++ struct qcom_nandc_data *this = chip->priv;
++ int real_len = min_t(size_t, len, this->buf_count - this->buf_start);
++
++ memcpy(this->data_buffer + this->buf_start, buf, real_len);
++
++ this->buf_start += real_len;
++}
++
++/* we support only one external chip for now */
++static void qcom_nandc_select_chip(struct mtd_info *mtd, int chipnr)
++{
++ struct nand_chip *chip = mtd->priv;
++ struct qcom_nandc_data *this = chip->priv;
++
++ if (chipnr <= 0)
++ return;
++
++ dev_warn(this->dev, "invalid chip select\n");
++}
++
++/*
++ * NAND controller page layout info
++ *
++ * |-----------------------| |---------------------------------|
++ * | xx.......xx| | *********xx.......xx|
++ * | DATA xx..ECC..xx| | DATA **SPARE**xx..ECC..xx|
++ * | (516) xx.......xx| | (516-n*4) **(n*4)**xx.......xx|
++ * | xx.......xx| | *********xx.......xx|
++ * |-----------------------| |---------------------------------|
++ * codeword 1,2..n-1 codeword n
++ * <---(528/532 Bytes)----> <-------(528/532 Bytes)---------->
++ *
++ * n = number of codewords in the page
++ * . = ECC bytes
++ * * = spare bytes
++ * x = unused/reserved bytes
++ *
++ * 2K page: n = 4, spare = 16 bytes
++ * 4K page: n = 8, spare = 32 bytes
++ * 8K page: n = 16, spare = 64 bytes
++ *
++ * the qcom nand controller operates at a sub page/codeword level. each
++ * codeword is 528 and 532 bytes for 4 bit and 8 bit ECC modes respectively.
++ * the number of ECC bytes vary based on the ECC strength and the bus width.
++ *
++ * the first n - 1 codewords contains 516 bytes of user data, the remaining
++ * 12/16 bytes consist of ECC and reserved data. The nth codeword contains
++ * both user data and spare(oobavail) bytes that sum up to 516 bytes.
++ *
++ * the layout described above is used by the controller when the ECC block is
++ * enabled. When we read a page with ECC enabled, the unused/reserved bytes are
++ * skipped and not copied to our internal buffer. therefore, the nand_ecclayout
++ * layouts defined below doesn't consider the positions occupied by the reserved
++ * bytes
++ *
++ * when the ECC block is disabled, one unused byte (or two for 16 bit bus width)
++ * in the last codeword is the position of bad block marker. the bad block
++ * marker cannot be accessed when ECC is enabled.
++ *
++ */
++
++/*
++ * Layouts for different page sizes and ecc modes. We skip the eccpos field
++ * since it isn't needed for this driver
++ */
++
++/* 2K page, 4 bit ECC */
++static struct nand_ecclayout layout_oob_64 = {
++ .eccbytes = 40,
++ .oobfree = {
++ { 30, 16 },
++ },
++};
++
++/* 4K page, 4 bit ECC, 8/16 bit bus width */
++static struct nand_ecclayout layout_oob_128 = {
++ .eccbytes = 80,
++ .oobfree = {
++ { 70, 32 },
++ },
++};
++
++/* 4K page, 8 bit ECC, 8 bit bus width */
++static struct nand_ecclayout layout_oob_224_x8 = {
++ .eccbytes = 104,
++ .oobfree = {
++ { 91, 32 },
++ },
++};
++
++/* 4K page, 8 bit ECC, 16 bit bus width */
++static struct nand_ecclayout layout_oob_224_x16 = {
++ .eccbytes = 112,
++ .oobfree = {
++ { 98, 32 },
++ },
++};
++
++/* 8K page, 4 bit ECC, 8/16 bit bus width */
++static struct nand_ecclayout layout_oob_256 = {
++ .eccbytes = 160,
++ .oobfree = {
++ { 151, 64 },
++ },
++};
++
++/*
++ * this is called before scan_ident, we do some minimal configurations so
++ * that reading ID and ONFI params work
++ */
++static void qcom_nandc_pre_init(struct qcom_nandc_data *this)
++{
++ /* kill onenand */
++ nandc_write(this, SFLASHC_BURST_CFG, 0);
++
++ /* enable ADM DMA */
++ nandc_write(this, NAND_FLASH_CHIP_SELECT, DM_EN);
++
++ /* save the original values of these registers */
++ this->cmd1 = nandc_read(this, NAND_DEV_CMD1);
++ this->vld = nandc_read(this, NAND_DEV_CMD_VLD);
++
++ /* initial status value */
++ this->status = NAND_STATUS_READY | NAND_STATUS_WP;
++}
++
++static int qcom_nandc_ecc_init(struct qcom_nandc_data *this)
++{
++ struct mtd_info *mtd = &this->mtd;
++ struct nand_chip *chip = &this->chip;
++ struct nand_ecc_ctrl *ecc = &chip->ecc;
++ int cwperpage;
++ bool wide_bus;
++
++ /* the nand controller fetches codewords/chunks of 512 bytes */
++ cwperpage = mtd->writesize >> 9;
++
++ ecc->strength = this->ecc_strength;
++
++ wide_bus = chip->options & NAND_BUSWIDTH_16 ? true : false;
++
++ if (ecc->strength >= 8) {
++ /* 8 bit ECC defaults to BCH ECC on all platforms */
++ ecc->bytes = wide_bus ? 14 : 13;
++ } else {
++ /*
++ * if the controller supports BCH for 4 bit ECC, the controller
++ * uses lesser bytes for ECC. If RS is used, the ECC bytes is
++ * always 10 bytes
++ */
++ if (this->ecc_modes & ECC_BCH_4BIT)
++ ecc->bytes = wide_bus ? 8 : 7;
++ else
++ ecc->bytes = 10;
++ }
++
++ /* each step consists of 512 bytes of data */
++ ecc->size = NANDC_STEP_SIZE;
++
++ ecc->read_page = qcom_nandc_read_page;
++ ecc->read_oob = qcom_nandc_read_oob;
++ ecc->write_page = qcom_nandc_write_page;
++ ecc->write_oob = qcom_nandc_write_oob;
++
++ /*
++ * the bad block marker is readable only when we read the page with ECC
++ * disabled. all the ops above run with ECC enabled. We need raw read
++ * and write function for oob in order to access bad block marker.
++ */
++ ecc->read_oob_raw = qcom_nandc_read_oob_raw;
++ ecc->write_oob_raw = qcom_nandc_write_oob_raw;
++
++ switch (mtd->oobsize) {
++ case 64:
++ ecc->layout = &layout_oob_64;
++ break;
++ case 128:
++ ecc->layout = &layout_oob_128;
++ break;
++ case 224:
++ if (wide_bus)
++ ecc->layout = &layout_oob_224_x16;
++ else
++ ecc->layout = &layout_oob_224_x8;
++ break;
++ case 256:
++ ecc->layout = &layout_oob_256;
++ break;
++ default:
++ dev_err(this->dev, "unsupported NAND device, oobsize %d\n",
++ mtd->oobsize);
++ return -ENODEV;
++ }
++
++ ecc->mode = NAND_ECC_HW;
++
++ /* enable ecc by default */
++ this->use_ecc = true;
++
++ return 0;
++}
++
++static void qcom_nandc_hw_post_init(struct qcom_nandc_data *this)
++{
++ struct mtd_info *mtd = &this->mtd;
++ struct nand_chip *chip = &this->chip;
++ struct nand_ecc_ctrl *ecc = &chip->ecc;
++ int cwperpage = mtd->writesize / ecc->size;
++ int spare_bytes, bad_block_byte;
++ bool wide_bus;
++ int ecc_mode = 0;
++
++ wide_bus = chip->options & NAND_BUSWIDTH_16 ? true : false;
++
++ if (ecc->strength >= 8) {
++ this->cw_size = 532;
++
++ spare_bytes = wide_bus ? 0 : 2;
++
++ this->bch_enabled = true;
++ ecc_mode = 1;
++ } else {
++ this->cw_size = 528;
++
++ if (this->ecc_modes & ECC_BCH_4BIT) {
++ spare_bytes = wide_bus ? 2 : 4;
++
++ this->bch_enabled = true;
++ ecc_mode = 0;
++ } else {
++ spare_bytes = wide_bus ? 0 : 1;
++ }
++ }
++
++ /*
++ * DATA_UD_BYTES varies based on whether the read/write command protects
++ * spare data with ECC too. We protect spare data by default, so we set
++ * it to main + spare data, which are 512 and 4 bytes respectively.
++ */
++ this->cw_data = 516;
++
++ bad_block_byte = mtd->writesize - this->cw_size * (cwperpage - 1) + 1;
++
++ this->cfg0 = (cwperpage - 1) << CW_PER_PAGE
++ | this->cw_data << UD_SIZE_BYTES
++ | 0 << DISABLE_STATUS_AFTER_WRITE
++ | 5 << NUM_ADDR_CYCLES
++ | ecc->bytes << ECC_PARITY_SIZE_BYTES_RS
++ | 0 << STATUS_BFR_READ
++ | 1 << SET_RD_MODE_AFTER_STATUS
++ | spare_bytes << SPARE_SIZE_BYTES;
++
++ this->cfg1 = 7 << NAND_RECOVERY_CYCLES
++ | 0 << CS_ACTIVE_BSY
++ | bad_block_byte << BAD_BLOCK_BYTE_NUM
++ | 0 << BAD_BLOCK_IN_SPARE_AREA
++ | 2 << WR_RD_BSY_GAP
++ | wide_bus << WIDE_FLASH
++ | this->bch_enabled << ENABLE_BCH_ECC;
++
++ this->cfg0_raw = (cwperpage - 1) << CW_PER_PAGE
++ | this->cw_size << UD_SIZE_BYTES
++ | 5 << NUM_ADDR_CYCLES
++ | 0 << SPARE_SIZE_BYTES;
++
++ this->cfg1_raw = 7 << NAND_RECOVERY_CYCLES
++ | 0 << CS_ACTIVE_BSY
++ | 17 << BAD_BLOCK_BYTE_NUM
++ | 1 << BAD_BLOCK_IN_SPARE_AREA
++ | 2 << WR_RD_BSY_GAP
++ | wide_bus << WIDE_FLASH
++ | 1 << DEV0_CFG1_ECC_DISABLE;
++
++ this->ecc_bch_cfg = this->bch_enabled << ECC_CFG_ECC_DISABLE
++ | 0 << ECC_SW_RESET
++ | this->cw_data << ECC_NUM_DATA_BYTES
++ | 1 << ECC_FORCE_CLK_OPEN
++ | ecc_mode << ECC_MODE
++ | ecc->bytes << ECC_PARITY_SIZE_BYTES_BCH;
++
++ this->ecc_buf_cfg = 0x203 << NUM_STEPS;
++
++ this->clrflashstatus = FS_READY_BSY_N;
++ this->clrreadstatus = 0xc0;
++
++ dev_dbg(this->dev,
++ "cfg0 %x cfg1 %x ecc_buf_cfg %x ecc_bch cfg %x cw_size %d cw_data %d strength %d parity_bytes %d steps %d\n",
++ this->cfg0, this->cfg1, this->ecc_buf_cfg,
++ this->ecc_bch_cfg, this->cw_size, this->cw_data,
++ ecc->strength, ecc->bytes, cwperpage);
++}
++
++static int qcom_nandc_alloc(struct qcom_nandc_data *this)
++{
++ int r;
++
++ r = dma_set_coherent_mask(this->dev, DMA_BIT_MASK(32));
++ if (r) {
++ dev_err(this->dev, "failed to set DMA mask\n");
++ return r;
++ }
++
++ /*
++ * we use the internal buffer for reading ONFI params, reading small
++ * data like ID and status, and preforming read-copy-write operations
++ * when writing to a codeword partially. 532 is the maximum possible
++ * size of a codeword for our nand controller
++ */
++ this->buf_size = 532;
++
++ this->data_buffer = devm_kzalloc(this->dev, this->buf_size, GFP_KERNEL);
++ if (!this->data_buffer)
++ return -ENOMEM;
++
++ this->regs = devm_kzalloc(this->dev, sizeof(*this->regs), GFP_KERNEL);
++ if (!this->regs)
++ return -ENOMEM;
++
++ this->reg_read_buf = devm_kzalloc(this->dev,
++ MAX_REG_RD * sizeof(*this->reg_read_buf),
++ GFP_KERNEL);
++ if (!this->reg_read_buf)
++ return -ENOMEM;
++
++ INIT_LIST_HEAD(&this->list);
++
++ this->chan = dma_request_slave_channel(this->dev, "rxtx");
++ if (!this->chan) {
++ dev_err(this->dev, "failed to request slave channel\n");
++ return -ENODEV;
++ }
++
++ return 0;
++}
++
++static void qcom_nandc_unalloc(struct qcom_nandc_data *this)
++{
++ dma_release_channel(this->chan);
++}
++
++static int qcom_nandc_init(struct qcom_nandc_data *this)
++{
++ struct mtd_info *mtd = &this->mtd;
++ struct nand_chip *chip = &this->chip;
++ struct device_node *np = this->dev->of_node;
++ struct mtd_part_parser_data ppdata = { .of_node = np };
++ int r;
++
++ mtd->priv = chip;
++ mtd->name = "qcom-nandc";
++ mtd->owner = THIS_MODULE;
++
++ chip->priv = this;
++
++ chip->cmdfunc = qcom_nandc_command;
++ chip->select_chip = qcom_nandc_select_chip;
++ chip->read_byte = qcom_nandc_read_byte;
++ chip->read_buf = qcom_nandc_read_buf;
++ chip->write_buf = qcom_nandc_write_buf;
++
++ chip->options |= NAND_NO_SUBPAGE_WRITE | NAND_USE_BOUNCE_BUFFER;
++ if (this->bus_width == 16)
++ chip->options |= NAND_BUSWIDTH_16;
++
++ chip->bbt_options = NAND_BBT_ACCESS_BBM_RAW;
++ if (of_get_nand_on_flash_bbt(np))
++ chip->bbt_options = NAND_BBT_USE_FLASH | NAND_BBT_NO_OOB;
++
++ qcom_nandc_pre_init(this);
++
++ r = nand_scan_ident(mtd, 1, NULL);
++ if (r)
++ return r;
++
++ r = qcom_nandc_ecc_init(this);
++ if (r)
++ return r;
++
++ qcom_nandc_hw_post_init(this);
++
++ r = nand_scan_tail(mtd);
++ if (r)
++ return r;
++
++ return mtd_device_parse_register(mtd, NULL, &ppdata, NULL, 0);
++}
++
++static int qcom_nandc_parse_dt(struct platform_device *pdev)
++{
++ struct qcom_nandc_data *this = platform_get_drvdata(pdev);
++ struct device_node *np = this->dev->of_node;
++ int r;
++
++ this->ecc_strength = of_get_nand_ecc_strength(np);
++ if (this->ecc_strength < 0) {
++ dev_warn(this->dev,
++ "incorrect ecc strength, setting to 4 bits/step\n");
++ this->ecc_strength = 4;
++ }
++
++ this->bus_width = of_get_nand_bus_width(np);
++ if (this->bus_width < 0) {
++ dev_warn(this->dev, "incorrect bus width, setting to 8\n");
++ this->bus_width = 8;
++ }
++
++ r = of_property_read_u32(np, "qcom,cmd-crci", &this->cmd_crci);
++ if (r) {
++ dev_err(this->dev, "command CRCI unspecified\n");
++ return r;
++ }
++
++ r = of_property_read_u32(np, "qcom,data-crci", &this->data_crci);
++ if (r) {
++ dev_err(this->dev, "data CRCI unspecified\n");
++ return r;
++ }
++
++ return 0;
++}
++
++static int qcom_nandc_probe(struct platform_device *pdev)
++{
++ struct qcom_nandc_data *this;
++ const struct of_device_id *match;
++ int r;
++
++ this = devm_kzalloc(&pdev->dev, sizeof(*this), GFP_KERNEL);
++ if (!this)
++ return -ENOMEM;
++
++ platform_set_drvdata(pdev, this);
++
++ this->pdev = pdev;
++ this->dev = &pdev->dev;
++
++ match = of_match_device(pdev->dev.driver->of_match_table, &pdev->dev);
++ if (!match) {
++ dev_err(&pdev->dev, "failed to match device\n");
++ return -ENODEV;
++ }
++
++ if (!match->data) {
++ dev_err(&pdev->dev, "failed to get device data\n");
++ return -ENODEV;
++ }
++
++ this->ecc_modes = (u32) match->data;
++
++ this->res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
++ this->base = devm_ioremap_resource(&pdev->dev, this->res);
++ if (IS_ERR(this->base))
++ return PTR_ERR(this->base);
++
++ this->core_clk = devm_clk_get(&pdev->dev, "core");
++ if (IS_ERR(this->core_clk))
++ return PTR_ERR(this->core_clk);
++
++ this->aon_clk = devm_clk_get(&pdev->dev, "aon");
++ if (IS_ERR(this->aon_clk))
++ return PTR_ERR(this->aon_clk);
++
++ r = qcom_nandc_parse_dt(pdev);
++ if (r)
++ return r;
++
++ r = qcom_nandc_alloc(this);
++ if (r)
++ return r;
++
++ r = clk_prepare_enable(this->core_clk);
++ if (r)
++ goto err_core_clk;
++
++ r = clk_prepare_enable(this->aon_clk);
++ if (r)
++ goto err_aon_clk;
++
++ r = qcom_nandc_init(this);
++ if (r)
++ goto err_init;
++
++ return 0;
++
++err_init:
++ clk_disable_unprepare(this->aon_clk);
++err_aon_clk:
++ clk_disable_unprepare(this->core_clk);
++err_core_clk:
++ qcom_nandc_unalloc(this);
++
++ return r;
++}
++
++static int qcom_nandc_remove(struct platform_device *pdev)
++{
++ struct qcom_nandc_data *this = platform_get_drvdata(pdev);
++
++ qcom_nandc_unalloc(this);
++
++ clk_disable_unprepare(this->aon_clk);
++ clk_disable_unprepare(this->core_clk);
++
++ return 0;
++}
++
++#define EBI2_NANDC_ECC_MODES (ECC_RS_4BIT | ECC_BCH_8BIT)
++
++/*
++ * data will hold a struct pointer containing more differences once we support
++ * more IPs
++ */
++static const struct of_device_id qcom_nandc_of_match[] = {
++ { .compatible = "qcom,ebi2-nandc",
++ .data = (void *) EBI2_NANDC_ECC_MODES,
++ },
++ {}
++};
++MODULE_DEVICE_TABLE(of, qcom_nandc_of_match);
++
++static struct platform_driver qcom_nandc_driver = {
++ .driver = {
++ .name = "qcom-nandc",
++ .of_match_table = qcom_nandc_of_match,
++ },
++ .probe = qcom_nandc_probe,
++ .remove = qcom_nandc_remove,
++};
++module_platform_driver(qcom_nandc_driver);
++
++MODULE_AUTHOR("Archit Taneja <architt@codeaurora.org>");
++MODULE_DESCRIPTION("Qualcomm NAND Controller driver");
++MODULE_LICENSE("GPL v2");
+--- a/drivers/mtd/nand/Makefile
++++ b/drivers/mtd/nand/Makefile
+@@ -50,5 +50,6 @@ obj-$(CONFIG_MTD_NAND_JZ4740) += jz4740
+ obj-$(CONFIG_MTD_NAND_GPMI_NAND) += gpmi-nand/
+ obj-$(CONFIG_MTD_NAND_XWAY) += xway_nand.o
+ obj-$(CONFIG_MTD_NAND_BCM47XXNFLASH) += bcm47xxnflash/
++obj-$(CONFIG_MTD_NAND_QCOM) += qcom_nandc.o
+
+ nand-objs := nand_base.o nand_bbt.o nand_timings.o
projects / openwrt / staging / lynxis / omap.git / blobdiff