--- /dev/null
+From cd3af4fa73ab25353f0865ebe8e0d2af1fd2a50b Mon Sep 17 00:00:00 2001
+From: Phil Elwell <phil@raspberrypi.org>
+Date: Tue, 19 Feb 2019 22:06:59 +0000
+Subject: [PATCH] PCI: brcmstb: Add MSI capability
+
+This commit adds MSI to the Broadcom STB PCIe host controller. It does
+not add MSIX since that functionality is not in the HW. The MSI
+controller is physically located within the PCIe block, however, there
+is no reason why the MSI controller could not be moved elsewhere in
+the future.
+
+Since the internal Brcmstb MSI controller is intertwined with the PCIe
+controller, it is not its own platform device but rather part of the
+PCIe platform device.
+
+Signed-off-by: Jim Quinlan <jim2101024@gmail.com>
+---
+ drivers/pci/controller/pcie-brcmstb.c | 374 ++++++++++++++++++++++++--
+ 1 file changed, 353 insertions(+), 21 deletions(-)
+
+--- a/drivers/pci/controller/pcie-brcmstb.c
++++ b/drivers/pci/controller/pcie-brcmstb.c
+@@ -1,6 +1,7 @@
+ // SPDX-License-Identifier: GPL-2.0
+ /* Copyright (C) 2009 - 2017 Broadcom */
+
++#include <linux/bitops.h>
+ #include <linux/clk.h>
+ #include <linux/compiler.h>
+ #include <linux/delay.h>
+@@ -9,11 +10,13 @@
+ #include <linux/interrupt.h>
+ #include <linux/io.h>
+ #include <linux/ioport.h>
++#include <linux/irqchip/chained_irq.h>
+ #include <linux/irqdomain.h>
+ #include <linux/kernel.h>
+ #include <linux/list.h>
+ #include <linux/log2.h>
+ #include <linux/module.h>
++#include <linux/msi.h>
+ #include <linux/of_address.h>
+ #include <linux/of_irq.h>
+ #include <linux/of_pci.h>
+@@ -47,6 +50,9 @@
+ #define PCIE_MISC_RC_BAR2_CONFIG_LO 0x4034
+ #define PCIE_MISC_RC_BAR2_CONFIG_HI 0x4038
+ #define PCIE_MISC_RC_BAR3_CONFIG_LO 0x403c
++#define PCIE_MISC_MSI_BAR_CONFIG_LO 0x4044
++#define PCIE_MISC_MSI_BAR_CONFIG_HI 0x4048
++#define PCIE_MISC_MSI_DATA_CONFIG 0x404c
+ #define PCIE_MISC_PCIE_CTRL 0x4064
+ #define PCIE_MISC_PCIE_STATUS 0x4068
+ #define PCIE_MISC_REVISION 0x406c
+@@ -55,6 +61,7 @@
+ #define PCIE_MISC_CPU_2_PCIE_MEM_WIN0_LIMIT_HI 0x4084
+ #define PCIE_MISC_HARD_PCIE_HARD_DEBUG 0x4204
+ #define PCIE_INTR2_CPU_BASE 0x4300
++#define PCIE_MSI_INTR2_BASE 0x4500
+
+ /*
+ * Broadcom Settop Box PCIe Register Field shift and mask info. The
+@@ -115,6 +122,8 @@
+
+ #define BRCM_NUM_PCIE_OUT_WINS 0x4
+ #define BRCM_MAX_SCB 0x4
++#define BRCM_INT_PCI_MSI_NR 32
++#define BRCM_PCIE_HW_REV_33 0x0303
+
+ #define BRCM_MSI_TARGET_ADDR_LT_4GB 0x0fffffffcULL
+ #define BRCM_MSI_TARGET_ADDR_GT_4GB 0xffffffffcULL
+@@ -203,6 +212,33 @@ struct brcm_window {
+ dma_addr_t size;
+ };
+
++struct brcm_msi {
++ struct device *dev;
++ void __iomem *base;
++ struct device_node *dn;
++ struct irq_domain *msi_domain;
++ struct irq_domain *inner_domain;
++ struct mutex lock; /* guards the alloc/free operations */
++ u64 target_addr;
++ int irq;
++
++ /* intr_base is the base pointer for interrupt status/set/clr regs */
++ void __iomem *intr_base;
++
++ /* intr_legacy_mask indicates how many bits are MSI interrupts */
++ u32 intr_legacy_mask;
++
++ /*
++ * intr_legacy_offset indicates bit position of MSI_01. It is
++ * to map the register bit position to a hwirq that starts at 0.
++ */
++ u32 intr_legacy_offset;
++
++ /* used indicates which MSI interrupts have been alloc'd */
++ unsigned long used;
++ unsigned int rev;
++};
++
+ /* Internal PCIe Host Controller Information.*/
+ struct brcm_pcie {
+ struct device *dev;
+@@ -217,7 +253,10 @@ struct brcm_pcie {
+ int num_out_wins;
+ bool ssc;
+ int gen;
++ u64 msi_target_addr;
+ struct brcm_window out_wins[BRCM_NUM_PCIE_OUT_WINS];
++ struct brcm_msi *msi;
++ bool msi_internal;
+ unsigned int rev;
+ const int *reg_offsets;
+ const int *reg_field_info;
+@@ -225,9 +264,9 @@ struct brcm_pcie {
+ };
+
+ struct pcie_cfg_data {
+- const int *reg_field_info;
+- const int *offsets;
+- const enum pcie_type type;
++ const int *reg_field_info;
++ const int *offsets;
++ const enum pcie_type type;
+ };
+
+ static const int pcie_reg_field_info[] = {
+@@ -828,6 +867,267 @@ static void brcm_pcie_set_outbound_win(s
+ }
+ }
+
++static struct irq_chip brcm_msi_irq_chip = {
++ .name = "Brcm_MSI",
++ .irq_mask = pci_msi_mask_irq,
++ .irq_unmask = pci_msi_unmask_irq,
++};
++
++static struct msi_domain_info brcm_msi_domain_info = {
++ .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
++ MSI_FLAG_PCI_MSIX),
++ .chip = &brcm_msi_irq_chip,
++};
++
++static void brcm_pcie_msi_isr(struct irq_desc *desc)
++{
++ struct irq_chip *chip = irq_desc_get_chip(desc);
++ struct brcm_msi *msi;
++ unsigned long status, virq;
++ u32 mask, bit, hwirq;
++ struct device *dev;
++
++ chained_irq_enter(chip, desc);
++ msi = irq_desc_get_handler_data(desc);
++ mask = msi->intr_legacy_mask;
++ dev = msi->dev;
++
++ while ((status = bcm_readl(msi->intr_base + STATUS) & mask)) {
++ for_each_set_bit(bit, &status, BRCM_INT_PCI_MSI_NR) {
++ /* clear the interrupt */
++ bcm_writel(1 << bit, msi->intr_base + CLR);
++
++ /* Account for legacy interrupt offset */
++ hwirq = bit - msi->intr_legacy_offset;
++
++ virq = irq_find_mapping(msi->inner_domain, hwirq);
++ if (virq) {
++ if (msi->used & (1 << hwirq))
++ generic_handle_irq(virq);
++ else
++ dev_info(dev, "unhandled MSI %d\n",
++ hwirq);
++ } else {
++ /* Unknown MSI, just clear it */
++ dev_dbg(dev, "unexpected MSI\n");
++ }
++ }
++ }
++ chained_irq_exit(chip, desc);
++}
++
++static void brcm_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
++{
++ struct brcm_msi *msi = irq_data_get_irq_chip_data(data);
++ u32 temp;
++
++ msg->address_lo = lower_32_bits(msi->target_addr);
++ msg->address_hi = upper_32_bits(msi->target_addr);
++ temp = bcm_readl(msi->base + PCIE_MISC_MSI_DATA_CONFIG);
++ msg->data = ((temp >> 16) & (temp & 0xffff)) | data->hwirq;
++}
++
++static int brcm_msi_set_affinity(struct irq_data *irq_data,
++ const struct cpumask *mask, bool force)
++{
++ return -EINVAL;
++}
++
++static struct irq_chip brcm_msi_bottom_irq_chip = {
++ .name = "Brcm_MSI",
++ .irq_compose_msi_msg = brcm_compose_msi_msg,
++ .irq_set_affinity = brcm_msi_set_affinity,
++};
++
++static int brcm_msi_alloc(struct brcm_msi *msi)
++{
++ int bit, hwirq;
++
++ mutex_lock(&msi->lock);
++ bit = ~msi->used ? ffz(msi->used) : -1;
++
++ if (bit >= 0 && bit < BRCM_INT_PCI_MSI_NR) {
++ msi->used |= (1 << bit);
++ hwirq = bit - msi->intr_legacy_offset;
++ } else {
++ hwirq = -ENOSPC;
++ }
++
++ mutex_unlock(&msi->lock);
++ return hwirq;
++}
++
++static void brcm_msi_free(struct brcm_msi *msi, unsigned long hwirq)
++{
++ mutex_lock(&msi->lock);
++ msi->used &= ~(1 << (hwirq + msi->intr_legacy_offset));
++ mutex_unlock(&msi->lock);
++}
++
++static int brcm_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
++ unsigned int nr_irqs, void *args)
++{
++ struct brcm_msi *msi = domain->host_data;
++ int hwirq;
++
++ hwirq = brcm_msi_alloc(msi);
++
++ if (hwirq < 0)
++ return hwirq;
++
++ irq_domain_set_info(domain, virq, (irq_hw_number_t)hwirq,
++ &brcm_msi_bottom_irq_chip, domain->host_data,
++ handle_simple_irq, NULL, NULL);
++ return 0;
++}
++
++static void brcm_irq_domain_free(struct irq_domain *domain,
++ unsigned int virq, unsigned int nr_irqs)
++{
++ struct irq_data *d = irq_domain_get_irq_data(domain, virq);
++ struct brcm_msi *msi = irq_data_get_irq_chip_data(d);
++
++ brcm_msi_free(msi, d->hwirq);
++}
++
++static void brcm_msi_set_regs(struct brcm_msi *msi)
++{
++ u32 data_val, msi_lo, msi_hi;
++
++ if (msi->rev >= BRCM_PCIE_HW_REV_33) {
++ /*
++ * ffe0 -- least sig 5 bits are 0 indicating 32 msgs
++ * 6540 -- this is our arbitrary unique data value
++ */
++ data_val = 0xffe06540;
++ } else {
++ /*
++ * fff8 -- least sig 3 bits are 0 indicating 8 msgs
++ * 6540 -- this is our arbitrary unique data value
++ */
++ data_val = 0xfff86540;
++ }
++
++ /*
++ * Make sure we are not masking MSIs. Note that MSIs can be masked,
++ * but that occurs on the PCIe EP device
++ */
++ bcm_writel(0xffffffff & msi->intr_legacy_mask,
++ msi->intr_base + MASK_CLR);
++
++ msi_lo = lower_32_bits(msi->target_addr);
++ msi_hi = upper_32_bits(msi->target_addr);
++ /*
++ * The 0 bit of PCIE_MISC_MSI_BAR_CONFIG_LO is repurposed to MSI
++ * enable, which we set to 1.
++ */
++ bcm_writel(msi_lo | 1, msi->base + PCIE_MISC_MSI_BAR_CONFIG_LO);
++ bcm_writel(msi_hi, msi->base + PCIE_MISC_MSI_BAR_CONFIG_HI);
++ bcm_writel(data_val, msi->base + PCIE_MISC_MSI_DATA_CONFIG);
++}
++
++static const struct irq_domain_ops msi_domain_ops = {
++ .alloc = brcm_irq_domain_alloc,
++ .free = brcm_irq_domain_free,
++};
++
++static int brcm_allocate_domains(struct brcm_msi *msi)
++{
++ struct fwnode_handle *fwnode = of_node_to_fwnode(msi->dn);
++ struct device *dev = msi->dev;
++
++ msi->inner_domain = irq_domain_add_linear(NULL, BRCM_INT_PCI_MSI_NR,
++ &msi_domain_ops, msi);
++ if (!msi->inner_domain) {
++ dev_err(dev, "failed to create IRQ domain\n");
++ return -ENOMEM;
++ }
++
++ msi->msi_domain = pci_msi_create_irq_domain(fwnode,
++ &brcm_msi_domain_info,
++ msi->inner_domain);
++ if (!msi->msi_domain) {
++ dev_err(dev, "failed to create MSI domain\n");
++ irq_domain_remove(msi->inner_domain);
++ return -ENOMEM;
++ }
++
++ return 0;
++}
++
++static void brcm_free_domains(struct brcm_msi *msi)
++{
++ irq_domain_remove(msi->msi_domain);
++ irq_domain_remove(msi->inner_domain);
++}
++
++static void brcm_msi_remove(struct brcm_pcie *pcie)
++{
++ struct brcm_msi *msi = pcie->msi;
++
++ if (!msi)
++ return;
++ irq_set_chained_handler(msi->irq, NULL);
++ irq_set_handler_data(msi->irq, NULL);
++ brcm_free_domains(msi);
++}
++
++static int brcm_pcie_enable_msi(struct brcm_pcie *pcie)
++{
++ struct brcm_msi *msi;
++ int irq, ret;
++ struct device *dev = pcie->dev;
++
++ irq = irq_of_parse_and_map(dev->of_node, 1);
++ if (irq <= 0) {
++ dev_err(dev, "cannot map msi intr\n");
++ return -ENODEV;
++ }
++
++ msi = devm_kzalloc(dev, sizeof(struct brcm_msi), GFP_KERNEL);
++ if (!msi)
++ return -ENOMEM;
++
++ msi->dev = dev;
++ msi->base = pcie->base;
++ msi->rev = pcie->rev;
++ msi->dn = pcie->dn;
++ msi->target_addr = pcie->msi_target_addr;
++ msi->irq = irq;
++
++ ret = brcm_allocate_domains(msi);
++ if (ret)
++ return ret;
++
++ irq_set_chained_handler_and_data(msi->irq, brcm_pcie_msi_isr, msi);
++
++ if (msi->rev >= BRCM_PCIE_HW_REV_33) {
++ msi->intr_base = msi->base + PCIE_MSI_INTR2_BASE;
++ /*
++ * This version of PCIe hw has only 32 intr bits
++ * starting at bit position 0.
++ */
++ msi->intr_legacy_mask = 0xffffffff;
++ msi->intr_legacy_offset = 0x0;
++ msi->used = 0x0;
++
++ } else {
++ msi->intr_base = msi->base + PCIE_INTR2_CPU_BASE;
++ /*
++ * This version of PCIe hw has only 8 intr bits starting
++ * at bit position 24.
++ */
++ msi->intr_legacy_mask = 0xff000000;
++ msi->intr_legacy_offset = 24;
++ msi->used = 0x00ffffff;
++ }
++
++ brcm_msi_set_regs(msi);
++ pcie->msi = msi;
++
++ return 0;
++}
++
+ /* Configuration space read/write support */
+ static int cfg_index(int busnr, int devfn, int reg)
+ {
+@@ -1072,6 +1372,7 @@ static int brcm_pcie_setup(struct brcm_p
+ u16 nlw, cls, lnksta;
+ bool ssc_good = false;
+ struct device *dev = pcie->dev;
++ u64 msi_target_addr;
+
+ /* Reset the bridge */
+ brcm_pcie_bridge_sw_init_set(pcie, 1);
+@@ -1116,27 +1417,24 @@ static int brcm_pcie_setup(struct brcm_p
+ * The PCIe host controller by design must set the inbound
+ * viewport to be a contiguous arrangement of all of the
+ * system's memory. In addition, its size mut be a power of
+- * two. To further complicate matters, the viewport must
+- * start on a pcie-address that is aligned on a multiple of its
+- * size. If a portion of the viewport does not represent
+- * system memory -- e.g. 3GB of memory requires a 4GB viewport
+- * -- we can map the outbound memory in or after 3GB and even
+- * though the viewport will overlap the outbound memory the
+- * controller will know to send outbound memory downstream and
+- * everything else upstream.
++ * two. Further, the MSI target address must NOT be placed
++ * inside this region, as the decoding logic will consider its
++ * address to be inbound memory traffic. To further
++ * complicate matters, the viewport must start on a
++ * pcie-address that is aligned on a multiple of its size.
++ * If a portion of the viewport does not represent system
++ * memory -- e.g. 3GB of memory requires a 4GB viewport --
++ * we can map the outbound memory in or after 3GB and even
++ * though the viewport will overlap the outbound memory
++ * the controller will know to send outbound memory downstream
++ * and everything else upstream.
+ */
+ rc_bar2_size = roundup_pow_of_two_64(total_mem_size);
+
+- /*
+- * Set simple configuration based on memory sizes
+- * only. We always start the viewport at address 0.
+- */
+- rc_bar2_offset = 0;
+-
+ if (dma_ranges) {
+ /*
+ * The best-case scenario is to place the inbound
+- * region in the first 4GB of pci-space, as some
++ * region in the first 4GB of pcie-space, as some
+ * legacy devices can only address 32bits.
+ * We would also like to put the MSI under 4GB
+ * as well, since some devices require a 32bit
+@@ -1145,6 +1443,14 @@ static int brcm_pcie_setup(struct brcm_p
+ if (total_mem_size <= 0xc0000000ULL &&
+ rc_bar2_size <= 0x100000000ULL) {
+ rc_bar2_offset = 0;
++ /* If the viewport is less then 4GB we can fit
++ * the MSI target address under 4GB. Otherwise
++ * put it right below 64GB.
++ */
++ msi_target_addr =
++ (rc_bar2_size == 0x100000000ULL)
++ ? BRCM_MSI_TARGET_ADDR_GT_4GB
++ : BRCM_MSI_TARGET_ADDR_LT_4GB;
+ } else {
+ /*
+ * The system memory is 4GB or larger so we
+@@ -1154,8 +1460,12 @@ static int brcm_pcie_setup(struct brcm_p
+ * start it at the 1x multiple of its size
+ */
+ rc_bar2_offset = rc_bar2_size;
+- }
+
++ /* Since we are starting the viewport at 4GB or
++ * higher, put the MSI target address below 4GB
++ */
++ msi_target_addr = BRCM_MSI_TARGET_ADDR_LT_4GB;
++ }
+ } else {
+ /*
+ * Set simple configuration based on memory sizes
+@@ -1163,7 +1473,12 @@ static int brcm_pcie_setup(struct brcm_p
+ * and set the MSI target address accordingly.
+ */
+ rc_bar2_offset = 0;
++
++ msi_target_addr = (rc_bar2_size >= 0x100000000ULL)
++ ? BRCM_MSI_TARGET_ADDR_GT_4GB
++ : BRCM_MSI_TARGET_ADDR_LT_4GB;
+ }
++ pcie->msi_target_addr = msi_target_addr;
+
+ tmp = lower_32_bits(rc_bar2_offset);
+ tmp = INSERT_FIELD(tmp, PCIE_MISC_RC_BAR2_CONFIG_LO, SIZE,
+@@ -1333,6 +1648,9 @@ static int brcm_pcie_resume(struct devic
+ if (ret)
+ return ret;
+
++ if (pcie->msi && pcie->msi_internal)
++ brcm_msi_set_regs(pcie->msi);
++
+ pcie->suspended = false;
+
+ return 0;
+@@ -1340,6 +1658,7 @@ static int brcm_pcie_resume(struct devic
+
+ static void _brcm_pcie_remove(struct brcm_pcie *pcie)
+ {
++ brcm_msi_remove(pcie);
+ turn_off(pcie);
+ clk_disable_unprepare(pcie->clk);
+ clk_put(pcie->clk);
+@@ -1368,7 +1687,7 @@ MODULE_DEVICE_TABLE(of, brcm_pcie_match)
+
+ static int brcm_pcie_probe(struct platform_device *pdev)
+ {
+- struct device_node *dn = pdev->dev.of_node;
++ struct device_node *dn = pdev->dev.of_node, *msi_dn;
+ const struct of_device_id *of_id;
+ const struct pcie_cfg_data *data;
+ int ret;
+@@ -1448,6 +1767,20 @@ static int brcm_pcie_probe(struct platfo
+ if (ret)
+ goto fail;
+
++ msi_dn = of_parse_phandle(pcie->dn, "msi-parent", 0);
++ /* Use the internal MSI if no msi-parent property */
++ if (!msi_dn)
++ msi_dn = pcie->dn;
++
++ if (pci_msi_enabled() && msi_dn == pcie->dn) {
++ ret = brcm_pcie_enable_msi(pcie);
++ if (ret)
++ dev_err(pcie->dev,
++ "probe of internal MSI failed: %d)", ret);
++ else
++ pcie->msi_internal = true;
++ }
++
+ list_splice_init(&pcie->resources, &bridge->windows);
+ bridge->dev.parent = &pdev->dev;
+ bridge->busnr = 0;
+@@ -1470,7 +1803,6 @@ static int brcm_pcie_probe(struct platfo
+ pcie->root_bus = bridge->bus;
+
+ return 0;
+-
+ fail:
+ _brcm_pcie_remove(pcie);
+ return ret;
projects / openwrt / staging / dedeckeh.git / blobdiff