+++ /dev/null
-From 0d6e214f5a257f9b53619ef8aa3b6e767189bdcf Mon Sep 17 00:00:00 2001
-From: Fugang Duan <fugang.duan@nxp.com>
-Date: Wed, 11 Sep 2019 16:21:06 +0800
-Subject: [PATCH] tty: serial: fsl_lpuart: enable dma mode for imx8qxp
-
-imx8qxp lpuart support eDMA for dma mode, support EOP (end-of-packet)
-feature. But eDMA cannot detect the correct DADDR for current major
-loop in cyclic mode, so it doesn't support cyclic mode.
-
-The patch is to enable lpuart prep slave sg dma mode for imx8qxp.
-
-Signed-off-by: Fugang Duan <fugang.duan@nxp.com>
----
- drivers/tty/serial/fsl_lpuart.c | 280 +++++++++++++++++++++++++++++++---------
- 1 file changed, 219 insertions(+), 61 deletions(-)
-
---- a/drivers/tty/serial/fsl_lpuart.c
-+++ b/drivers/tty/serial/fsl_lpuart.c
-@@ -131,6 +131,7 @@
- #define UARTBAUD_M10 0x20000000
- #define UARTBAUD_TDMAE 0x00800000
- #define UARTBAUD_RDMAE 0x00200000
-+#define UARTBAUD_RIDMAE 0x00100000
- #define UARTBAUD_MATCFG 0x00400000
- #define UARTBAUD_BOTHEDGE 0x00020000
- #define UARTBAUD_RESYNCDIS 0x00010000
-@@ -179,7 +180,7 @@
- #define UARTCTRL_SBK 0x00010000
- #define UARTCTRL_MA1IE 0x00008000
- #define UARTCTRL_MA2IE 0x00004000
--#define UARTCTRL_IDLECFG 0x00000100
-+#define UARTCTRL_IDLECFG_OFF 0x8
- #define UARTCTRL_LOOPS 0x00000080
- #define UARTCTRL_DOZEEN 0x00000040
- #define UARTCTRL_RSRC 0x00000020
-@@ -197,6 +198,7 @@
- #define UARTDATA_MASK 0x3ff
-
- #define UARTMODIR_IREN 0x00020000
-+#define UARTMODIR_RTSWATER_S 0x8
- #define UARTMODIR_TXCTSSRC 0x00000020
- #define UARTMODIR_TXCTSC 0x00000010
- #define UARTMODIR_RXRTSE 0x00000008
-@@ -210,6 +212,8 @@
- #define UARTFIFO_RXUF 0x00010000
- #define UARTFIFO_TXFLUSH 0x00008000
- #define UARTFIFO_RXFLUSH 0x00004000
-+#define UARTFIFO_RXIDEN_MASK 0x7
-+#define UARTFIFO_RXIDEN_OFF 10
- #define UARTFIFO_TXOFE 0x00000200
- #define UARTFIFO_RXUFE 0x00000100
- #define UARTFIFO_TXFE 0x00000080
-@@ -226,6 +230,9 @@
- #define UARTWATER_TXWATER_OFF 0
- #define UARTWATER_RXWATER_OFF 16
-
-+#define UARTFIFO_RXIDEN_RDRF 0x3
-+#define UARTCTRL_IDLECFG 0x7
-+
- /* Rx DMA timeout in ms, which is used to calculate Rx ring buffer size */
- #define DMA_RX_TIMEOUT (10)
-
-@@ -254,6 +261,9 @@ struct lpuart_port {
- unsigned int txfifo_size;
- unsigned int rxfifo_size;
-
-+ u8 rx_watermark;
-+ bool dma_eeop;
-+ bool rx_dma_cyclic;
- bool lpuart_dma_tx_use;
- bool lpuart_dma_rx_use;
- struct dma_chan *dma_tx_chan;
-@@ -279,33 +289,45 @@ struct lpuart_soc_data {
- enum lpuart_type devtype;
- char iotype;
- u8 reg_off;
-+ u8 rx_watermark;
-+ bool rx_dma_cyclic;
- };
-
- static const struct lpuart_soc_data vf_data = {
- .devtype = VF610_LPUART,
- .iotype = UPIO_MEM,
-+ .rx_watermark = 1,
-+ .rx_dma_cyclic = true,
- };
-
- static const struct lpuart_soc_data ls1021a_data = {
- .devtype = LS1021A_LPUART,
- .iotype = UPIO_MEM32BE,
-+ .rx_watermark = 0,
-+ .rx_dma_cyclic = true,
- };
-
- static const struct lpuart_soc_data ls1028a_data = {
- .devtype = LS1028A_LPUART,
- .iotype = UPIO_MEM32,
-+ .rx_watermark = 0,
-+ .rx_dma_cyclic = true,
- };
-
- static struct lpuart_soc_data imx7ulp_data = {
- .devtype = IMX7ULP_LPUART,
- .iotype = UPIO_MEM32,
- .reg_off = IMX_REG_OFF,
-+ .rx_watermark = 0,
-+ .rx_dma_cyclic = true,
- };
-
- static struct lpuart_soc_data imx8qxp_data = {
- .devtype = IMX8QXP_LPUART,
- .iotype = UPIO_MEM32,
- .reg_off = IMX_REG_OFF,
-+ .rx_watermark = 31,
-+ .rx_dma_cyclic = false,
- };
-
- static const struct of_device_id lpuart_dt_ids[] = {
-@@ -320,6 +342,7 @@ MODULE_DEVICE_TABLE(of, lpuart_dt_ids);
-
- /* Forward declare this for the dma callbacks*/
- static void lpuart_dma_tx_complete(void *arg);
-+static int lpuart_sched_rx_dma(struct lpuart_port *sport);
-
- static inline bool is_layerscape_lpuart(struct lpuart_port *sport)
- {
-@@ -1011,19 +1034,15 @@ static irqreturn_t lpuart32_int(int irq,
- if ((sts & UARTSTAT_TDRE) && !sport->lpuart_dma_tx_use)
- lpuart32_txint(sport);
-
-+ if (sport->lpuart_dma_rx_use && sport->dma_eeop)
-+ sts &= ~UARTSTAT_IDLE;
-+
- lpuart32_write(&sport->port, sts, UARTSTAT);
- return IRQ_HANDLED;
- }
-
--static void lpuart_copy_rx_to_tty(struct lpuart_port *sport)
-+static void lpuart_rx_error_stat(struct lpuart_port *sport)
- {
-- struct tty_port *port = &sport->port.state->port;
-- struct dma_tx_state state;
-- enum dma_status dmastat;
-- struct circ_buf *ring = &sport->rx_ring;
-- unsigned long flags;
-- int count = 0;
--
- if (lpuart_is_32(sport)) {
- unsigned long sr = lpuart32_read(&sport->port, UARTSTAT);
-
-@@ -1075,8 +1094,21 @@ static void lpuart_copy_rx_to_tty(struct
- writeb(cr2, sport->port.membase + UARTCR2);
- }
- }
-+}
-+
-+static void lpuart_copy_rx_to_tty(struct lpuart_port *sport)
-+{
-+ struct tty_port *port = &sport->port.state->port;
-+ struct dma_tx_state state;
-+ enum dma_status dmastat;
-+ struct circ_buf *ring = &sport->rx_ring;
-+ unsigned long flags;
-+ int count = 0;
-
-- async_tx_ack(sport->dma_rx_desc);
-+ if (!is_imx8qxp_lpuart(sport)) {
-+ lpuart_rx_error_stat(sport);
-+ async_tx_ack(sport->dma_rx_desc);
-+ }
-
- spin_lock_irqsave(&sport->port.lock, flags);
-
-@@ -1139,7 +1171,33 @@ static void lpuart_copy_rx_to_tty(struct
- spin_unlock_irqrestore(&sport->port.lock, flags);
-
- tty_flip_buffer_push(port);
-- mod_timer(&sport->lpuart_timer, jiffies + sport->dma_rx_timeout);
-+
-+ if (!sport->dma_eeop)
-+ mod_timer(&sport->lpuart_timer,
-+ jiffies + sport->dma_rx_timeout);
-+}
-+
-+static void lpuart_dma_rx_post_handler(struct lpuart_port *sport)
-+{
-+ unsigned long flags;
-+ unsigned long rxcount;
-+
-+ spin_lock_irqsave(&sport->port.lock, flags);
-+
-+ /* For end of packet, clear the idle flag to avoid to trigger
-+ * the next transfer. Only i.MX8x lpuart support EEOP.
-+ */
-+ if (sport->dma_eeop && lpuart_is_32(sport)) {
-+ rxcount = lpuart32_read(&sport->port, UARTWATER);
-+ rxcount = rxcount >> UARTWATER_RXCNT_OFF;
-+ if (!rxcount)
-+ lpuart32_write(&sport->port, UARTSTAT_IDLE, UARTSTAT);
-+ }
-+
-+ lpuart_sched_rx_dma(sport);
-+
-+ spin_unlock_irqrestore(&sport->port.lock, flags);
-+
- }
-
- static void lpuart_dma_rx_complete(void *arg)
-@@ -1147,6 +1205,8 @@ static void lpuart_dma_rx_complete(void
- struct lpuart_port *sport = arg;
-
- lpuart_copy_rx_to_tty(sport);
-+ if (!sport->rx_dma_cyclic)
-+ lpuart_dma_rx_post_handler(sport);
- }
-
- static void lpuart_timer_func(struct timer_list *t)
-@@ -1154,13 +1214,78 @@ static void lpuart_timer_func(struct tim
- struct lpuart_port *sport = from_timer(sport, t, lpuart_timer);
-
- lpuart_copy_rx_to_tty(sport);
-+ if (!sport->rx_dma_cyclic) {
-+ dmaengine_terminate_async(sport->dma_rx_chan);
-+ lpuart_dma_rx_post_handler(sport);
-+ }
- }
-
--static inline int lpuart_start_rx_dma(struct lpuart_port *sport)
-+static int lpuart_sched_rxdma_cyclic(struct lpuart_port *sport)
-+{
-+ sport->dma_rx_desc = dmaengine_prep_dma_cyclic(sport->dma_rx_chan,
-+ sg_dma_address(&sport->rx_sgl),
-+ sport->rx_sgl.length,
-+ sport->rx_sgl.length / 2,
-+ DMA_DEV_TO_MEM,
-+ DMA_PREP_INTERRUPT);
-+ if (!sport->dma_rx_desc) {
-+ dev_err(sport->port.dev, "Cannot prepare cyclic DMA\n");
-+ return -EFAULT;
-+ }
-+
-+ return 0;
-+}
-+
-+static int lpuart_sched_rxdma_slave_sg(struct lpuart_port *sport)
-+{
-+ dma_sync_sg_for_device(sport->port.dev, &sport->rx_sgl, 1,
-+ DMA_FROM_DEVICE);
-+ sport->dma_rx_desc = dmaengine_prep_slave_sg(sport->dma_rx_chan,
-+ &sport->rx_sgl,
-+ 1,
-+ DMA_DEV_TO_MEM,
-+ DMA_PREP_INTERRUPT);
-+ if (!sport->dma_rx_desc) {
-+ dev_err(sport->port.dev, "Cannot prepare slave_sg DMA\n");
-+ return -EFAULT;
-+ }
-+ sport->rx_ring.tail = 0;
-+ sport->rx_ring.head = 0;
-+
-+ return 0;
-+}
-+
-+static int lpuart_sched_rx_dma(struct lpuart_port *sport)
-+{
-+ unsigned long temp;
-+ int ret;
-+
-+ if (sport->rx_dma_cyclic)
-+ ret = lpuart_sched_rxdma_cyclic(sport);
-+ else
-+ ret = lpuart_sched_rxdma_slave_sg(sport);
-+
-+ sport->dma_rx_desc->callback = lpuart_dma_rx_complete;
-+ sport->dma_rx_desc->callback_param = sport;
-+ sport->dma_rx_cookie = dmaengine_submit(sport->dma_rx_desc);
-+ dma_async_issue_pending(sport->dma_rx_chan);
-+
-+ if (lpuart_is_32(sport)) {
-+ temp = lpuart32_read(&sport->port, UARTBAUD);
-+ if (sport->dma_eeop)
-+ temp |= UARTBAUD_RIDMAE;
-+ temp |= UARTBAUD_RDMAE;
-+ lpuart32_write(&sport->port, temp, UARTBAUD);
-+ } else {
-+ writeb(readb(sport->port.membase + UARTCR5) | UARTCR5_RDMAS,
-+ sport->port.membase + UARTCR5);
-+ }
-+
-+ return ret;
-+}
-+
-+static void lpuart_get_rx_dma_rng_len(struct lpuart_port *sport)
- {
-- struct dma_slave_config dma_rx_sconfig = {};
-- struct circ_buf *ring = &sport->rx_ring;
-- int ret, nent;
- int bits, baud;
- struct tty_port *port = &sport->port.state->port;
- struct tty_struct *tty = port->tty;
-@@ -1180,6 +1305,18 @@ static inline int lpuart_start_rx_dma(st
- sport->rx_dma_rng_buf_len = (1 << (fls(sport->rx_dma_rng_buf_len) - 1));
- if (sport->rx_dma_rng_buf_len < 16)
- sport->rx_dma_rng_buf_len = 16;
-+}
-+
-+static inline int lpuart_start_rx_dma(struct lpuart_port *sport)
-+{
-+ struct dma_slave_config dma_rx_sconfig = {};
-+ struct circ_buf *ring = &sport->rx_ring;
-+ int ret, nent;
-+
-+ if (!sport->dma_eeop)
-+ lpuart_get_rx_dma_rng_len(sport);
-+ else
-+ sport->rx_dma_rng_buf_len = PAGE_SIZE;
-
- ring->buf = kzalloc(sport->rx_dma_rng_buf_len, GFP_ATOMIC);
- if (!ring->buf)
-@@ -1205,32 +1342,7 @@ static inline int lpuart_start_rx_dma(st
- return ret;
- }
-
-- sport->dma_rx_desc = dmaengine_prep_dma_cyclic(sport->dma_rx_chan,
-- sg_dma_address(&sport->rx_sgl),
-- sport->rx_sgl.length,
-- sport->rx_sgl.length / 2,
-- DMA_DEV_TO_MEM,
-- DMA_PREP_INTERRUPT);
-- if (!sport->dma_rx_desc) {
-- dev_err(sport->port.dev, "Cannot prepare cyclic DMA\n");
-- return -EFAULT;
-- }
--
-- sport->dma_rx_desc->callback = lpuart_dma_rx_complete;
-- sport->dma_rx_desc->callback_param = sport;
-- sport->dma_rx_cookie = dmaengine_submit(sport->dma_rx_desc);
-- dma_async_issue_pending(sport->dma_rx_chan);
--
-- if (lpuart_is_32(sport)) {
-- unsigned long temp = lpuart32_read(&sport->port, UARTBAUD);
--
-- lpuart32_write(&sport->port, temp | UARTBAUD_RDMAE, UARTBAUD);
-- } else {
-- writeb(readb(sport->port.membase + UARTCR5) | UARTCR5_RDMAS,
-- sport->port.membase + UARTCR5);
-- }
--
-- return 0;
-+ return lpuart_sched_rx_dma(sport);
- }
-
- static void lpuart_dma_rx_free(struct uart_port *port)
-@@ -1416,8 +1528,10 @@ static void lpuart_setup_watermark(struc
- writeb(UARTSFIFO_RXUF, sport->port.membase + UARTSFIFO);
- }
-
-+ if (uart_console(&sport->port))
-+ sport->rx_watermark = 1;
- writeb(0, sport->port.membase + UARTTWFIFO);
-- writeb(1, sport->port.membase + UARTRWFIFO);
-+ writeb(sport->rx_watermark, sport->port.membase + UARTRWFIFO);
-
- /* Restore cr2 */
- writeb(cr2_saved, sport->port.membase + UARTCR2);
-@@ -1438,6 +1552,7 @@ static void lpuart32_setup_watermark(str
- {
- unsigned long val, ctrl;
- unsigned long ctrl_saved;
-+ unsigned long rxiden_cnt;
-
- ctrl = lpuart32_read(&sport->port, UARTCTRL);
- ctrl_saved = ctrl;
-@@ -1449,12 +1564,26 @@ static void lpuart32_setup_watermark(str
- val = lpuart32_read(&sport->port, UARTFIFO);
- val |= UARTFIFO_TXFE | UARTFIFO_RXFE;
- val |= UARTFIFO_TXFLUSH | UARTFIFO_RXFLUSH;
-+ val &= ~(UARTFIFO_RXIDEN_MASK << UARTFIFO_RXIDEN_OFF);
-+ rxiden_cnt = sport->dma_eeop ? 0 : UARTFIFO_RXIDEN_RDRF;
-+ val |= ((rxiden_cnt & UARTFIFO_RXIDEN_MASK) <<
-+ UARTFIFO_RXIDEN_OFF);
- lpuart32_write(&sport->port, val, UARTFIFO);
-
- /* set the watermark */
-- val = (0x1 << UARTWATER_RXWATER_OFF) | (0x0 << UARTWATER_TXWATER_OFF);
-+ if (uart_console(&sport->port))
-+ sport->rx_watermark = 1;
-+ val = (sport->rx_watermark << UARTWATER_RXWATER_OFF) |
-+ (0x0 << UARTWATER_TXWATER_OFF);
- lpuart32_write(&sport->port, val, UARTWATER);
-
-+ /* set RTS watermark */
-+ if (!uart_console(&sport->port)) {
-+ val = lpuart32_read(&sport->port, UARTMODIR);
-+ val = (sport->rxfifo_size >> 1) << UARTMODIR_RTSWATER_S;
-+ lpuart32_write(&sport->port, val, UARTMODIR);
-+ }
-+
- /* Restore cr2 */
- lpuart32_write(&sport->port, ctrl_saved, UARTCTRL);
- }
-@@ -1466,17 +1595,29 @@ static void lpuart32_setup_watermark_ena
- lpuart32_setup_watermark(sport);
-
- temp = lpuart32_read(&sport->port, UARTCTRL);
-- temp |= UARTCTRL_RE | UARTCTRL_TE | UARTCTRL_ILIE;
-+ temp |= UARTCTRL_RE | UARTCTRL_TE;
-+ temp |= UARTCTRL_IDLECFG << UARTCTRL_IDLECFG_OFF;
- lpuart32_write(&sport->port, temp, UARTCTRL);
- }
-
- static void rx_dma_timer_init(struct lpuart_port *sport)
- {
-+ if (sport->dma_eeop)
-+ return;
-+
- timer_setup(&sport->lpuart_timer, lpuart_timer_func, 0);
- sport->lpuart_timer.expires = jiffies + sport->dma_rx_timeout;
- add_timer(&sport->lpuart_timer);
- }
-
-+static void lpuart_del_timer_sync(struct lpuart_port *sport)
-+{
-+ if (sport->dma_eeop)
-+ return;
-+
-+ del_timer_sync(&sport->lpuart_timer);
-+}
-+
- static void lpuart_tx_dma_startup(struct lpuart_port *sport)
- {
- u32 uartbaud;
-@@ -1540,19 +1681,23 @@ static int lpuart_startup(struct uart_po
- return 0;
- }
-
-+static void lpuart32_hw_disable(struct lpuart_port *sport)
-+{
-+ unsigned long temp;
-+
-+ temp = lpuart32_read(&sport->port, UARTCTRL);
-+ temp &= ~(UARTCTRL_RIE | UARTCTRL_ILIE | UARTCTRL_RE |
-+ UARTCTRL_TIE | UARTCTRL_TE);
-+ lpuart32_write(&sport->port, temp, UARTCTRL);
-+}
-+
- static void lpuart32_configure(struct lpuart_port *sport)
- {
- unsigned long temp;
-
-- if (sport->lpuart_dma_rx_use) {
-- /* RXWATER must be 0 */
-- temp = lpuart32_read(&sport->port, UARTWATER);
-- temp &= ~(UARTWATER_WATER_MASK << UARTWATER_RXWATER_OFF);
-- lpuart32_write(&sport->port, temp, UARTWATER);
-- }
- temp = lpuart32_read(&sport->port, UARTCTRL);
- if (!sport->lpuart_dma_rx_use)
-- temp |= UARTCTRL_RIE;
-+ temp |= UARTCTRL_RIE | UARTCTRL_ILIE;
- if (!sport->lpuart_dma_tx_use)
- temp |= UARTCTRL_TIE;
- lpuart32_write(&sport->port, temp, UARTCTRL);
-@@ -1596,12 +1741,12 @@ static int lpuart32_startup(struct uart_
-
- spin_lock_irqsave(&sport->port.lock, flags);
-
-- lpuart32_setup_watermark_enable(sport);
--
-+ lpuart32_hw_disable(sport);
-
- lpuart_rx_dma_startup(sport);
- lpuart_tx_dma_startup(sport);
-
-+ lpuart32_setup_watermark_enable(sport);
- lpuart32_configure(sport);
-
- spin_unlock_irqrestore(&sport->port.lock, flags);
-@@ -1611,7 +1756,7 @@ static int lpuart32_startup(struct uart_
- static void lpuart_dma_shutdown(struct lpuart_port *sport)
- {
- if (sport->lpuart_dma_rx_use) {
-- del_timer_sync(&sport->lpuart_timer);
-+ lpuart_del_timer_sync(sport);
- lpuart_dma_rx_free(&sport->port);
- }
-
-@@ -1652,11 +1797,22 @@ static void lpuart32_shutdown(struct uar
-
- spin_lock_irqsave(&port->lock, flags);
-
-+ /* clear statue */
-+ temp = lpuart32_read(&sport->port, UARTSTAT);
-+ lpuart32_write(&sport->port, temp, UARTSTAT);
-+
-+ /* disable Rx/Tx DMA */
-+ temp = lpuart32_read(port, UARTBAUD);
-+ temp &= ~(UARTBAUD_TDMAE | UARTBAUD_RDMAE | UARTBAUD_RIDMAE);
-+ lpuart32_write(port, temp, UARTBAUD);
-+
- /* disable Rx/Tx and interrupts */
- temp = lpuart32_read(port, UARTCTRL);
-- temp &= ~(UARTCTRL_TE | UARTCTRL_RE |
-- UARTCTRL_TIE | UARTCTRL_TCIE | UARTCTRL_RIE);
-+ temp &= ~(UARTCTRL_TE | UARTCTRL_RE | UARTCTRL_TIE |
-+ UARTCTRL_TCIE | UARTCTRL_RIE | UARTCTRL_ILIE |
-+ UARTCTRL_LOOPS);
- lpuart32_write(port, temp, UARTCTRL);
-+ lpuart32_write(port, 0, UARTMODIR);
-
- spin_unlock_irqrestore(&port->lock, flags);
-
-@@ -1753,10 +1909,10 @@ lpuart_set_termios(struct uart_port *por
- * baud rate and restart Rx DMA path.
- *
- * Since timer function acqures sport->port.lock, need to stop before
-- * acquring same lock because otherwise del_timer_sync() can deadlock.
-+ * acquring same lock because otherwise lpuart_del_timer_sync() can deadlock.
- */
- if (old && sport->lpuart_dma_rx_use) {
-- del_timer_sync(&sport->lpuart_timer);
-+ lpuart_del_timer_sync(sport);
- lpuart_dma_rx_free(&sport->port);
- }
-
-@@ -1968,10 +2124,10 @@ lpuart32_set_termios(struct uart_port *p
- * baud rate and restart Rx DMA path.
- *
- * Since timer function acqures sport->port.lock, need to stop before
-- * acquring same lock because otherwise del_timer_sync() can deadlock.
-+ * acquring same lock because otherwise lpuart_del_timer_sync() can deadlock.
- */
- if (old && sport->lpuart_dma_rx_use) {
-- del_timer_sync(&sport->lpuart_timer);
-+ lpuart_del_timer_sync(sport);
- lpuart_dma_rx_free(&sport->port);
- }
-
-@@ -2483,6 +2639,10 @@ static int lpuart_probe(struct platform_
- sport->port.dev = &pdev->dev;
- sport->port.type = PORT_LPUART;
- sport->devtype = sdata->devtype;
-+ sport->rx_dma_cyclic = sdata->rx_dma_cyclic;
-+ sport->rx_watermark = sdata->rx_watermark;
-+ sport->dma_eeop = is_imx8qxp_lpuart(sport);
-+
- ret = platform_get_irq(pdev, 0);
- if (ret < 0)
- return ret;
-@@ -2645,7 +2805,7 @@ static int lpuart_suspend(struct device
- * Rx DMA path before suspend and start Rx DMA path on resume.
- */
- if (irq_wake) {
-- del_timer_sync(&sport->lpuart_timer);
-+ lpuart_del_timer_sync(sport);
- lpuart_dma_rx_free(&sport->port);
- }
-
projects / openwrt / openwrt.git / blobdiff