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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/tty/serial/fsl_lpuart.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/tty/serial/fsl_lpuart.c')
-rw-r--r--drivers/tty/serial/fsl_lpuart.c2961
1 files changed, 2961 insertions, 0 deletions
diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
new file mode 100644
index 000000000..c5a9b89c4
--- /dev/null
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -0,0 +1,2961 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Freescale lpuart serial port driver
+ *
+ * Copyright 2012-2014 Freescale Semiconductor, Inc.
+ */
+
+#include <linux/clk.h>
+#include <linux/console.h>
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/dmapool.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_dma.h>
+#include <linux/serial_core.h>
+#include <linux/slab.h>
+#include <linux/tty_flip.h>
+
+/* All registers are 8-bit width */
+#define UARTBDH 0x00
+#define UARTBDL 0x01
+#define UARTCR1 0x02
+#define UARTCR2 0x03
+#define UARTSR1 0x04
+#define UARTCR3 0x06
+#define UARTDR 0x07
+#define UARTCR4 0x0a
+#define UARTCR5 0x0b
+#define UARTMODEM 0x0d
+#define UARTPFIFO 0x10
+#define UARTCFIFO 0x11
+#define UARTSFIFO 0x12
+#define UARTTWFIFO 0x13
+#define UARTTCFIFO 0x14
+#define UARTRWFIFO 0x15
+
+#define UARTBDH_LBKDIE 0x80
+#define UARTBDH_RXEDGIE 0x40
+#define UARTBDH_SBR_MASK 0x1f
+
+#define UARTCR1_LOOPS 0x80
+#define UARTCR1_RSRC 0x20
+#define UARTCR1_M 0x10
+#define UARTCR1_WAKE 0x08
+#define UARTCR1_ILT 0x04
+#define UARTCR1_PE 0x02
+#define UARTCR1_PT 0x01
+
+#define UARTCR2_TIE 0x80
+#define UARTCR2_TCIE 0x40
+#define UARTCR2_RIE 0x20
+#define UARTCR2_ILIE 0x10
+#define UARTCR2_TE 0x08
+#define UARTCR2_RE 0x04
+#define UARTCR2_RWU 0x02
+#define UARTCR2_SBK 0x01
+
+#define UARTSR1_TDRE 0x80
+#define UARTSR1_TC 0x40
+#define UARTSR1_RDRF 0x20
+#define UARTSR1_IDLE 0x10
+#define UARTSR1_OR 0x08
+#define UARTSR1_NF 0x04
+#define UARTSR1_FE 0x02
+#define UARTSR1_PE 0x01
+
+#define UARTCR3_R8 0x80
+#define UARTCR3_T8 0x40
+#define UARTCR3_TXDIR 0x20
+#define UARTCR3_TXINV 0x10
+#define UARTCR3_ORIE 0x08
+#define UARTCR3_NEIE 0x04
+#define UARTCR3_FEIE 0x02
+#define UARTCR3_PEIE 0x01
+
+#define UARTCR4_MAEN1 0x80
+#define UARTCR4_MAEN2 0x40
+#define UARTCR4_M10 0x20
+#define UARTCR4_BRFA_MASK 0x1f
+#define UARTCR4_BRFA_OFF 0
+
+#define UARTCR5_TDMAS 0x80
+#define UARTCR5_RDMAS 0x20
+
+#define UARTMODEM_RXRTSE 0x08
+#define UARTMODEM_TXRTSPOL 0x04
+#define UARTMODEM_TXRTSE 0x02
+#define UARTMODEM_TXCTSE 0x01
+
+#define UARTPFIFO_TXFE 0x80
+#define UARTPFIFO_FIFOSIZE_MASK 0x7
+#define UARTPFIFO_TXSIZE_OFF 4
+#define UARTPFIFO_RXFE 0x08
+#define UARTPFIFO_RXSIZE_OFF 0
+
+#define UARTCFIFO_TXFLUSH 0x80
+#define UARTCFIFO_RXFLUSH 0x40
+#define UARTCFIFO_RXOFE 0x04
+#define UARTCFIFO_TXOFE 0x02
+#define UARTCFIFO_RXUFE 0x01
+
+#define UARTSFIFO_TXEMPT 0x80
+#define UARTSFIFO_RXEMPT 0x40
+#define UARTSFIFO_RXOF 0x04
+#define UARTSFIFO_TXOF 0x02
+#define UARTSFIFO_RXUF 0x01
+
+/* 32-bit global registers only for i.MX7ULP/i.MX8x
+ * Used to reset all internal logic and registers, except the Global Register.
+ */
+#define UART_GLOBAL 0x8
+
+/* 32-bit register definition */
+#define UARTBAUD 0x00
+#define UARTSTAT 0x04
+#define UARTCTRL 0x08
+#define UARTDATA 0x0C
+#define UARTMATCH 0x10
+#define UARTMODIR 0x14
+#define UARTFIFO 0x18
+#define UARTWATER 0x1c
+
+#define UARTBAUD_MAEN1 0x80000000
+#define UARTBAUD_MAEN2 0x40000000
+#define UARTBAUD_M10 0x20000000
+#define UARTBAUD_TDMAE 0x00800000
+#define UARTBAUD_RDMAE 0x00200000
+#define UARTBAUD_MATCFG 0x00400000
+#define UARTBAUD_BOTHEDGE 0x00020000
+#define UARTBAUD_RESYNCDIS 0x00010000
+#define UARTBAUD_LBKDIE 0x00008000
+#define UARTBAUD_RXEDGIE 0x00004000
+#define UARTBAUD_SBNS 0x00002000
+#define UARTBAUD_SBR 0x00000000
+#define UARTBAUD_SBR_MASK 0x1fff
+#define UARTBAUD_OSR_MASK 0x1f
+#define UARTBAUD_OSR_SHIFT 24
+
+#define UARTSTAT_LBKDIF 0x80000000
+#define UARTSTAT_RXEDGIF 0x40000000
+#define UARTSTAT_MSBF 0x20000000
+#define UARTSTAT_RXINV 0x10000000
+#define UARTSTAT_RWUID 0x08000000
+#define UARTSTAT_BRK13 0x04000000
+#define UARTSTAT_LBKDE 0x02000000
+#define UARTSTAT_RAF 0x01000000
+#define UARTSTAT_TDRE 0x00800000
+#define UARTSTAT_TC 0x00400000
+#define UARTSTAT_RDRF 0x00200000
+#define UARTSTAT_IDLE 0x00100000
+#define UARTSTAT_OR 0x00080000
+#define UARTSTAT_NF 0x00040000
+#define UARTSTAT_FE 0x00020000
+#define UARTSTAT_PE 0x00010000
+#define UARTSTAT_MA1F 0x00008000
+#define UARTSTAT_M21F 0x00004000
+
+#define UARTCTRL_R8T9 0x80000000
+#define UARTCTRL_R9T8 0x40000000
+#define UARTCTRL_TXDIR 0x20000000
+#define UARTCTRL_TXINV 0x10000000
+#define UARTCTRL_ORIE 0x08000000
+#define UARTCTRL_NEIE 0x04000000
+#define UARTCTRL_FEIE 0x02000000
+#define UARTCTRL_PEIE 0x01000000
+#define UARTCTRL_TIE 0x00800000
+#define UARTCTRL_TCIE 0x00400000
+#define UARTCTRL_RIE 0x00200000
+#define UARTCTRL_ILIE 0x00100000
+#define UARTCTRL_TE 0x00080000
+#define UARTCTRL_RE 0x00040000
+#define UARTCTRL_RWU 0x00020000
+#define UARTCTRL_SBK 0x00010000
+#define UARTCTRL_MA1IE 0x00008000
+#define UARTCTRL_MA2IE 0x00004000
+#define UARTCTRL_IDLECFG 0x00000100
+#define UARTCTRL_LOOPS 0x00000080
+#define UARTCTRL_DOZEEN 0x00000040
+#define UARTCTRL_RSRC 0x00000020
+#define UARTCTRL_M 0x00000010
+#define UARTCTRL_WAKE 0x00000008
+#define UARTCTRL_ILT 0x00000004
+#define UARTCTRL_PE 0x00000002
+#define UARTCTRL_PT 0x00000001
+
+#define UARTDATA_NOISY 0x00008000
+#define UARTDATA_PARITYE 0x00004000
+#define UARTDATA_FRETSC 0x00002000
+#define UARTDATA_RXEMPT 0x00001000
+#define UARTDATA_IDLINE 0x00000800
+#define UARTDATA_MASK 0x3ff
+
+#define UARTMODIR_IREN 0x00020000
+#define UARTMODIR_TXCTSSRC 0x00000020
+#define UARTMODIR_TXCTSC 0x00000010
+#define UARTMODIR_RXRTSE 0x00000008
+#define UARTMODIR_TXRTSPOL 0x00000004
+#define UARTMODIR_TXRTSE 0x00000002
+#define UARTMODIR_TXCTSE 0x00000001
+
+#define UARTFIFO_TXEMPT 0x00800000
+#define UARTFIFO_RXEMPT 0x00400000
+#define UARTFIFO_TXOF 0x00020000
+#define UARTFIFO_RXUF 0x00010000
+#define UARTFIFO_TXFLUSH 0x00008000
+#define UARTFIFO_RXFLUSH 0x00004000
+#define UARTFIFO_TXOFE 0x00000200
+#define UARTFIFO_RXUFE 0x00000100
+#define UARTFIFO_TXFE 0x00000080
+#define UARTFIFO_FIFOSIZE_MASK 0x7
+#define UARTFIFO_TXSIZE_OFF 4
+#define UARTFIFO_RXFE 0x00000008
+#define UARTFIFO_RXSIZE_OFF 0
+#define UARTFIFO_DEPTH(x) (0x1 << ((x) ? ((x) + 1) : 0))
+
+#define UARTWATER_COUNT_MASK 0xff
+#define UARTWATER_TXCNT_OFF 8
+#define UARTWATER_RXCNT_OFF 24
+#define UARTWATER_WATER_MASK 0xff
+#define UARTWATER_TXWATER_OFF 0
+#define UARTWATER_RXWATER_OFF 16
+
+#define UART_GLOBAL_RST 0x2
+#define GLOBAL_RST_MIN_US 20
+#define GLOBAL_RST_MAX_US 40
+
+/* Rx DMA timeout in ms, which is used to calculate Rx ring buffer size */
+#define DMA_RX_TIMEOUT (10)
+
+#define DRIVER_NAME "fsl-lpuart"
+#define DEV_NAME "ttyLP"
+#define UART_NR 6
+
+/* IMX lpuart has four extra unused regs located at the beginning */
+#define IMX_REG_OFF 0x10
+
+enum lpuart_type {
+ VF610_LPUART,
+ LS1021A_LPUART,
+ LS1028A_LPUART,
+ IMX7ULP_LPUART,
+ IMX8QXP_LPUART,
+ IMXRT1050_LPUART,
+};
+
+struct lpuart_port {
+ struct uart_port port;
+ enum lpuart_type devtype;
+ struct clk *ipg_clk;
+ struct clk *baud_clk;
+ unsigned int txfifo_size;
+ unsigned int rxfifo_size;
+
+ u8 rx_watermark;
+ bool lpuart_dma_tx_use;
+ bool lpuart_dma_rx_use;
+ struct dma_chan *dma_tx_chan;
+ struct dma_chan *dma_rx_chan;
+ struct dma_async_tx_descriptor *dma_tx_desc;
+ struct dma_async_tx_descriptor *dma_rx_desc;
+ dma_cookie_t dma_tx_cookie;
+ dma_cookie_t dma_rx_cookie;
+ unsigned int dma_tx_bytes;
+ unsigned int dma_rx_bytes;
+ bool dma_tx_in_progress;
+ unsigned int dma_rx_timeout;
+ struct timer_list lpuart_timer;
+ struct scatterlist rx_sgl, tx_sgl[2];
+ struct circ_buf rx_ring;
+ int rx_dma_rng_buf_len;
+ unsigned int dma_tx_nents;
+ wait_queue_head_t dma_wait;
+ bool is_cs7; /* Set to true when character size is 7 */
+ /* and the parity is enabled */
+};
+
+struct lpuart_soc_data {
+ enum lpuart_type devtype;
+ char iotype;
+ u8 reg_off;
+ u8 rx_watermark;
+};
+
+static const struct lpuart_soc_data vf_data = {
+ .devtype = VF610_LPUART,
+ .iotype = UPIO_MEM,
+ .rx_watermark = 1,
+};
+
+static const struct lpuart_soc_data ls1021a_data = {
+ .devtype = LS1021A_LPUART,
+ .iotype = UPIO_MEM32BE,
+ .rx_watermark = 1,
+};
+
+static const struct lpuart_soc_data ls1028a_data = {
+ .devtype = LS1028A_LPUART,
+ .iotype = UPIO_MEM32,
+ .rx_watermark = 0,
+};
+
+static struct lpuart_soc_data imx7ulp_data = {
+ .devtype = IMX7ULP_LPUART,
+ .iotype = UPIO_MEM32,
+ .reg_off = IMX_REG_OFF,
+ .rx_watermark = 1,
+};
+
+static struct lpuart_soc_data imx8qxp_data = {
+ .devtype = IMX8QXP_LPUART,
+ .iotype = UPIO_MEM32,
+ .reg_off = IMX_REG_OFF,
+ .rx_watermark = 1,
+};
+static struct lpuart_soc_data imxrt1050_data = {
+ .devtype = IMXRT1050_LPUART,
+ .iotype = UPIO_MEM32,
+ .reg_off = IMX_REG_OFF,
+ .rx_watermark = 1,
+};
+
+static const struct of_device_id lpuart_dt_ids[] = {
+ { .compatible = "fsl,vf610-lpuart", .data = &vf_data, },
+ { .compatible = "fsl,ls1021a-lpuart", .data = &ls1021a_data, },
+ { .compatible = "fsl,ls1028a-lpuart", .data = &ls1028a_data, },
+ { .compatible = "fsl,imx7ulp-lpuart", .data = &imx7ulp_data, },
+ { .compatible = "fsl,imx8qxp-lpuart", .data = &imx8qxp_data, },
+ { .compatible = "fsl,imxrt1050-lpuart", .data = &imxrt1050_data},
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, lpuart_dt_ids);
+
+/* Forward declare this for the dma callbacks*/
+static void lpuart_dma_tx_complete(void *arg);
+
+static inline bool is_layerscape_lpuart(struct lpuart_port *sport)
+{
+ return (sport->devtype == LS1021A_LPUART ||
+ sport->devtype == LS1028A_LPUART);
+}
+
+static inline bool is_imx7ulp_lpuart(struct lpuart_port *sport)
+{
+ return sport->devtype == IMX7ULP_LPUART;
+}
+
+static inline bool is_imx8qxp_lpuart(struct lpuart_port *sport)
+{
+ return sport->devtype == IMX8QXP_LPUART;
+}
+
+static inline u32 lpuart32_read(struct uart_port *port, u32 off)
+{
+ switch (port->iotype) {
+ case UPIO_MEM32:
+ return readl(port->membase + off);
+ case UPIO_MEM32BE:
+ return ioread32be(port->membase + off);
+ default:
+ return 0;
+ }
+}
+
+static inline void lpuart32_write(struct uart_port *port, u32 val,
+ u32 off)
+{
+ switch (port->iotype) {
+ case UPIO_MEM32:
+ writel(val, port->membase + off);
+ break;
+ case UPIO_MEM32BE:
+ iowrite32be(val, port->membase + off);
+ break;
+ }
+}
+
+static int __lpuart_enable_clks(struct lpuart_port *sport, bool is_en)
+{
+ int ret = 0;
+
+ if (is_en) {
+ ret = clk_prepare_enable(sport->ipg_clk);
+ if (ret)
+ return ret;
+
+ ret = clk_prepare_enable(sport->baud_clk);
+ if (ret) {
+ clk_disable_unprepare(sport->ipg_clk);
+ return ret;
+ }
+ } else {
+ clk_disable_unprepare(sport->baud_clk);
+ clk_disable_unprepare(sport->ipg_clk);
+ }
+
+ return 0;
+}
+
+static unsigned int lpuart_get_baud_clk_rate(struct lpuart_port *sport)
+{
+ if (is_imx8qxp_lpuart(sport))
+ return clk_get_rate(sport->baud_clk);
+
+ return clk_get_rate(sport->ipg_clk);
+}
+
+#define lpuart_enable_clks(x) __lpuart_enable_clks(x, true)
+#define lpuart_disable_clks(x) __lpuart_enable_clks(x, false)
+
+static void lpuart_stop_tx(struct uart_port *port)
+{
+ unsigned char temp;
+
+ temp = readb(port->membase + UARTCR2);
+ temp &= ~(UARTCR2_TIE | UARTCR2_TCIE);
+ writeb(temp, port->membase + UARTCR2);
+}
+
+static void lpuart32_stop_tx(struct uart_port *port)
+{
+ unsigned long temp;
+
+ temp = lpuart32_read(port, UARTCTRL);
+ temp &= ~(UARTCTRL_TIE | UARTCTRL_TCIE);
+ lpuart32_write(port, temp, UARTCTRL);
+}
+
+static void lpuart_stop_rx(struct uart_port *port)
+{
+ unsigned char temp;
+
+ temp = readb(port->membase + UARTCR2);
+ writeb(temp & ~UARTCR2_RE, port->membase + UARTCR2);
+}
+
+static void lpuart32_stop_rx(struct uart_port *port)
+{
+ unsigned long temp;
+
+ temp = lpuart32_read(port, UARTCTRL);
+ lpuart32_write(port, temp & ~UARTCTRL_RE, UARTCTRL);
+}
+
+static void lpuart_dma_tx(struct lpuart_port *sport)
+{
+ struct circ_buf *xmit = &sport->port.state->xmit;
+ struct scatterlist *sgl = sport->tx_sgl;
+ struct device *dev = sport->port.dev;
+ struct dma_chan *chan = sport->dma_tx_chan;
+ int ret;
+
+ if (sport->dma_tx_in_progress)
+ return;
+
+ sport->dma_tx_bytes = uart_circ_chars_pending(xmit);
+
+ if (xmit->tail < xmit->head || xmit->head == 0) {
+ sport->dma_tx_nents = 1;
+ sg_init_one(sgl, xmit->buf + xmit->tail, sport->dma_tx_bytes);
+ } else {
+ sport->dma_tx_nents = 2;
+ sg_init_table(sgl, 2);
+ sg_set_buf(sgl, xmit->buf + xmit->tail,
+ UART_XMIT_SIZE - xmit->tail);
+ sg_set_buf(sgl + 1, xmit->buf, xmit->head);
+ }
+
+ ret = dma_map_sg(chan->device->dev, sgl, sport->dma_tx_nents,
+ DMA_TO_DEVICE);
+ if (!ret) {
+ dev_err(dev, "DMA mapping error for TX.\n");
+ return;
+ }
+
+ sport->dma_tx_desc = dmaengine_prep_slave_sg(chan, sgl,
+ ret, DMA_MEM_TO_DEV,
+ DMA_PREP_INTERRUPT);
+ if (!sport->dma_tx_desc) {
+ dma_unmap_sg(chan->device->dev, sgl, sport->dma_tx_nents,
+ DMA_TO_DEVICE);
+ dev_err(dev, "Cannot prepare TX slave DMA!\n");
+ return;
+ }
+
+ sport->dma_tx_desc->callback = lpuart_dma_tx_complete;
+ sport->dma_tx_desc->callback_param = sport;
+ sport->dma_tx_in_progress = true;
+ sport->dma_tx_cookie = dmaengine_submit(sport->dma_tx_desc);
+ dma_async_issue_pending(chan);
+}
+
+static bool lpuart_stopped_or_empty(struct uart_port *port)
+{
+ return uart_circ_empty(&port->state->xmit) || uart_tx_stopped(port);
+}
+
+static void lpuart_dma_tx_complete(void *arg)
+{
+ struct lpuart_port *sport = arg;
+ struct scatterlist *sgl = &sport->tx_sgl[0];
+ struct circ_buf *xmit = &sport->port.state->xmit;
+ struct dma_chan *chan = sport->dma_tx_chan;
+ unsigned long flags;
+
+ spin_lock_irqsave(&sport->port.lock, flags);
+ if (!sport->dma_tx_in_progress) {
+ spin_unlock_irqrestore(&sport->port.lock, flags);
+ return;
+ }
+
+ dma_unmap_sg(chan->device->dev, sgl, sport->dma_tx_nents,
+ DMA_TO_DEVICE);
+
+ xmit->tail = (xmit->tail + sport->dma_tx_bytes) & (UART_XMIT_SIZE - 1);
+
+ sport->port.icount.tx += sport->dma_tx_bytes;
+ sport->dma_tx_in_progress = false;
+ spin_unlock_irqrestore(&sport->port.lock, flags);
+
+ if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+ uart_write_wakeup(&sport->port);
+
+ if (waitqueue_active(&sport->dma_wait)) {
+ wake_up(&sport->dma_wait);
+ return;
+ }
+
+ spin_lock_irqsave(&sport->port.lock, flags);
+
+ if (!lpuart_stopped_or_empty(&sport->port))
+ lpuart_dma_tx(sport);
+
+ spin_unlock_irqrestore(&sport->port.lock, flags);
+}
+
+static dma_addr_t lpuart_dma_datareg_addr(struct lpuart_port *sport)
+{
+ switch (sport->port.iotype) {
+ case UPIO_MEM32:
+ return sport->port.mapbase + UARTDATA;
+ case UPIO_MEM32BE:
+ return sport->port.mapbase + UARTDATA + sizeof(u32) - 1;
+ }
+ return sport->port.mapbase + UARTDR;
+}
+
+static int lpuart_dma_tx_request(struct uart_port *port)
+{
+ struct lpuart_port *sport = container_of(port,
+ struct lpuart_port, port);
+ struct dma_slave_config dma_tx_sconfig = {};
+ int ret;
+
+ dma_tx_sconfig.dst_addr = lpuart_dma_datareg_addr(sport);
+ dma_tx_sconfig.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+ dma_tx_sconfig.dst_maxburst = 1;
+ dma_tx_sconfig.direction = DMA_MEM_TO_DEV;
+ ret = dmaengine_slave_config(sport->dma_tx_chan, &dma_tx_sconfig);
+
+ if (ret) {
+ dev_err(sport->port.dev,
+ "DMA slave config failed, err = %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static bool lpuart_is_32(struct lpuart_port *sport)
+{
+ return sport->port.iotype == UPIO_MEM32 ||
+ sport->port.iotype == UPIO_MEM32BE;
+}
+
+static void lpuart_flush_buffer(struct uart_port *port)
+{
+ struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
+ struct dma_chan *chan = sport->dma_tx_chan;
+ u32 val;
+
+ if (sport->lpuart_dma_tx_use) {
+ if (sport->dma_tx_in_progress) {
+ dma_unmap_sg(chan->device->dev, &sport->tx_sgl[0],
+ sport->dma_tx_nents, DMA_TO_DEVICE);
+ sport->dma_tx_in_progress = false;
+ }
+ dmaengine_terminate_async(chan);
+ }
+
+ if (lpuart_is_32(sport)) {
+ val = lpuart32_read(&sport->port, UARTFIFO);
+ val |= UARTFIFO_TXFLUSH | UARTFIFO_RXFLUSH;
+ lpuart32_write(&sport->port, val, UARTFIFO);
+ } else {
+ val = readb(sport->port.membase + UARTCFIFO);
+ val |= UARTCFIFO_TXFLUSH | UARTCFIFO_RXFLUSH;
+ writeb(val, sport->port.membase + UARTCFIFO);
+ }
+}
+
+static void lpuart_wait_bit_set(struct uart_port *port, unsigned int offset,
+ u8 bit)
+{
+ while (!(readb(port->membase + offset) & bit))
+ cpu_relax();
+}
+
+static void lpuart32_wait_bit_set(struct uart_port *port, unsigned int offset,
+ u32 bit)
+{
+ while (!(lpuart32_read(port, offset) & bit))
+ cpu_relax();
+}
+
+#if defined(CONFIG_CONSOLE_POLL)
+
+static int lpuart_poll_init(struct uart_port *port)
+{
+ struct lpuart_port *sport = container_of(port,
+ struct lpuart_port, port);
+ unsigned long flags;
+ unsigned char temp;
+
+ sport->port.fifosize = 0;
+
+ spin_lock_irqsave(&sport->port.lock, flags);
+ /* Disable Rx & Tx */
+ writeb(0, sport->port.membase + UARTCR2);
+
+ temp = readb(sport->port.membase + UARTPFIFO);
+ /* Enable Rx and Tx FIFO */
+ writeb(temp | UARTPFIFO_RXFE | UARTPFIFO_TXFE,
+ sport->port.membase + UARTPFIFO);
+
+ /* flush Tx and Rx FIFO */
+ writeb(UARTCFIFO_TXFLUSH | UARTCFIFO_RXFLUSH,
+ sport->port.membase + UARTCFIFO);
+
+ /* explicitly clear RDRF */
+ if (readb(sport->port.membase + UARTSR1) & UARTSR1_RDRF) {
+ readb(sport->port.membase + UARTDR);
+ writeb(UARTSFIFO_RXUF, sport->port.membase + UARTSFIFO);
+ }
+
+ writeb(0, sport->port.membase + UARTTWFIFO);
+ writeb(1, sport->port.membase + UARTRWFIFO);
+
+ /* Enable Rx and Tx */
+ writeb(UARTCR2_RE | UARTCR2_TE, sport->port.membase + UARTCR2);
+ spin_unlock_irqrestore(&sport->port.lock, flags);
+
+ return 0;
+}
+
+static void lpuart_poll_put_char(struct uart_port *port, unsigned char c)
+{
+ /* drain */
+ lpuart_wait_bit_set(port, UARTSR1, UARTSR1_TDRE);
+ writeb(c, port->membase + UARTDR);
+}
+
+static int lpuart_poll_get_char(struct uart_port *port)
+{
+ if (!(readb(port->membase + UARTSR1) & UARTSR1_RDRF))
+ return NO_POLL_CHAR;
+
+ return readb(port->membase + UARTDR);
+}
+
+static int lpuart32_poll_init(struct uart_port *port)
+{
+ unsigned long flags;
+ struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
+ u32 temp;
+
+ sport->port.fifosize = 0;
+
+ spin_lock_irqsave(&sport->port.lock, flags);
+
+ /* Disable Rx & Tx */
+ lpuart32_write(&sport->port, 0, UARTCTRL);
+
+ temp = lpuart32_read(&sport->port, UARTFIFO);
+
+ /* Enable Rx and Tx FIFO */
+ lpuart32_write(&sport->port, temp | UARTFIFO_RXFE | UARTFIFO_TXFE, UARTFIFO);
+
+ /* flush Tx and Rx FIFO */
+ lpuart32_write(&sport->port, UARTFIFO_TXFLUSH | UARTFIFO_RXFLUSH, UARTFIFO);
+
+ /* explicitly clear RDRF */
+ if (lpuart32_read(&sport->port, UARTSTAT) & UARTSTAT_RDRF) {
+ lpuart32_read(&sport->port, UARTDATA);
+ lpuart32_write(&sport->port, UARTFIFO_RXUF, UARTFIFO);
+ }
+
+ /* Enable Rx and Tx */
+ lpuart32_write(&sport->port, UARTCTRL_RE | UARTCTRL_TE, UARTCTRL);
+ spin_unlock_irqrestore(&sport->port.lock, flags);
+
+ return 0;
+}
+
+static void lpuart32_poll_put_char(struct uart_port *port, unsigned char c)
+{
+ lpuart32_wait_bit_set(port, UARTSTAT, UARTSTAT_TDRE);
+ lpuart32_write(port, c, UARTDATA);
+}
+
+static int lpuart32_poll_get_char(struct uart_port *port)
+{
+ if (!(lpuart32_read(port, UARTWATER) >> UARTWATER_RXCNT_OFF))
+ return NO_POLL_CHAR;
+
+ return lpuart32_read(port, UARTDATA);
+}
+#endif
+
+static inline void lpuart_transmit_buffer(struct lpuart_port *sport)
+{
+ struct circ_buf *xmit = &sport->port.state->xmit;
+
+ if (sport->port.x_char) {
+ writeb(sport->port.x_char, sport->port.membase + UARTDR);
+ sport->port.icount.tx++;
+ sport->port.x_char = 0;
+ return;
+ }
+
+ if (lpuart_stopped_or_empty(&sport->port)) {
+ lpuart_stop_tx(&sport->port);
+ return;
+ }
+
+ while (!uart_circ_empty(xmit) &&
+ (readb(sport->port.membase + UARTTCFIFO) < sport->txfifo_size)) {
+ writeb(xmit->buf[xmit->tail], sport->port.membase + UARTDR);
+ xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+ sport->port.icount.tx++;
+ }
+
+ if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+ uart_write_wakeup(&sport->port);
+
+ if (uart_circ_empty(xmit))
+ lpuart_stop_tx(&sport->port);
+}
+
+static inline void lpuart32_transmit_buffer(struct lpuart_port *sport)
+{
+ struct circ_buf *xmit = &sport->port.state->xmit;
+ unsigned long txcnt;
+
+ if (sport->port.x_char) {
+ lpuart32_write(&sport->port, sport->port.x_char, UARTDATA);
+ sport->port.icount.tx++;
+ sport->port.x_char = 0;
+ return;
+ }
+
+ if (lpuart_stopped_or_empty(&sport->port)) {
+ lpuart32_stop_tx(&sport->port);
+ return;
+ }
+
+ txcnt = lpuart32_read(&sport->port, UARTWATER);
+ txcnt = txcnt >> UARTWATER_TXCNT_OFF;
+ txcnt &= UARTWATER_COUNT_MASK;
+ while (!uart_circ_empty(xmit) && (txcnt < sport->txfifo_size)) {
+ lpuart32_write(&sport->port, xmit->buf[xmit->tail], UARTDATA);
+ xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+ sport->port.icount.tx++;
+ txcnt = lpuart32_read(&sport->port, UARTWATER);
+ txcnt = txcnt >> UARTWATER_TXCNT_OFF;
+ txcnt &= UARTWATER_COUNT_MASK;
+ }
+
+ if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+ uart_write_wakeup(&sport->port);
+
+ if (uart_circ_empty(xmit))
+ lpuart32_stop_tx(&sport->port);
+}
+
+static void lpuart_start_tx(struct uart_port *port)
+{
+ struct lpuart_port *sport = container_of(port,
+ struct lpuart_port, port);
+ unsigned char temp;
+
+ temp = readb(port->membase + UARTCR2);
+ writeb(temp | UARTCR2_TIE, port->membase + UARTCR2);
+
+ if (sport->lpuart_dma_tx_use) {
+ if (!lpuart_stopped_or_empty(port))
+ lpuart_dma_tx(sport);
+ } else {
+ if (readb(port->membase + UARTSR1) & UARTSR1_TDRE)
+ lpuart_transmit_buffer(sport);
+ }
+}
+
+static void lpuart32_start_tx(struct uart_port *port)
+{
+ struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
+ unsigned long temp;
+
+ if (sport->lpuart_dma_tx_use) {
+ if (!lpuart_stopped_or_empty(port))
+ lpuart_dma_tx(sport);
+ } else {
+ temp = lpuart32_read(port, UARTCTRL);
+ lpuart32_write(port, temp | UARTCTRL_TIE, UARTCTRL);
+
+ if (lpuart32_read(port, UARTSTAT) & UARTSTAT_TDRE)
+ lpuart32_transmit_buffer(sport);
+ }
+}
+
+/* return TIOCSER_TEMT when transmitter is not busy */
+static unsigned int lpuart_tx_empty(struct uart_port *port)
+{
+ struct lpuart_port *sport = container_of(port,
+ struct lpuart_port, port);
+ unsigned char sr1 = readb(port->membase + UARTSR1);
+ unsigned char sfifo = readb(port->membase + UARTSFIFO);
+
+ if (sport->dma_tx_in_progress)
+ return 0;
+
+ if (sr1 & UARTSR1_TC && sfifo & UARTSFIFO_TXEMPT)
+ return TIOCSER_TEMT;
+
+ return 0;
+}
+
+static unsigned int lpuart32_tx_empty(struct uart_port *port)
+{
+ struct lpuart_port *sport = container_of(port,
+ struct lpuart_port, port);
+ unsigned long stat = lpuart32_read(port, UARTSTAT);
+ unsigned long sfifo = lpuart32_read(port, UARTFIFO);
+ unsigned long ctrl = lpuart32_read(port, UARTCTRL);
+
+ if (sport->dma_tx_in_progress)
+ return 0;
+
+ /*
+ * LPUART Transmission Complete Flag may never be set while queuing a break
+ * character, so avoid checking for transmission complete when UARTCTRL_SBK
+ * is asserted.
+ */
+ if ((stat & UARTSTAT_TC && sfifo & UARTFIFO_TXEMPT) || ctrl & UARTCTRL_SBK)
+ return TIOCSER_TEMT;
+
+ return 0;
+}
+
+static void lpuart_txint(struct lpuart_port *sport)
+{
+ spin_lock(&sport->port.lock);
+ lpuart_transmit_buffer(sport);
+ spin_unlock(&sport->port.lock);
+}
+
+static void lpuart_rxint(struct lpuart_port *sport)
+{
+ unsigned int flg, ignored = 0, overrun = 0;
+ struct tty_port *port = &sport->port.state->port;
+ unsigned char rx, sr;
+
+ spin_lock(&sport->port.lock);
+
+ while (!(readb(sport->port.membase + UARTSFIFO) & UARTSFIFO_RXEMPT)) {
+ flg = TTY_NORMAL;
+ sport->port.icount.rx++;
+ /*
+ * to clear the FE, OR, NF, FE, PE flags,
+ * read SR1 then read DR
+ */
+ sr = readb(sport->port.membase + UARTSR1);
+ rx = readb(sport->port.membase + UARTDR);
+
+ if (uart_prepare_sysrq_char(&sport->port, rx))
+ continue;
+
+ if (sr & (UARTSR1_PE | UARTSR1_OR | UARTSR1_FE)) {
+ if (sr & UARTSR1_PE)
+ sport->port.icount.parity++;
+ else if (sr & UARTSR1_FE)
+ sport->port.icount.frame++;
+
+ if (sr & UARTSR1_OR)
+ overrun++;
+
+ if (sr & sport->port.ignore_status_mask) {
+ if (++ignored > 100)
+ goto out;
+ continue;
+ }
+
+ sr &= sport->port.read_status_mask;
+
+ if (sr & UARTSR1_PE)
+ flg = TTY_PARITY;
+ else if (sr & UARTSR1_FE)
+ flg = TTY_FRAME;
+
+ if (sr & UARTSR1_OR)
+ flg = TTY_OVERRUN;
+
+ sport->port.sysrq = 0;
+ }
+
+ if (tty_insert_flip_char(port, rx, flg) == 0)
+ sport->port.icount.buf_overrun++;
+ }
+
+out:
+ if (overrun) {
+ sport->port.icount.overrun += overrun;
+
+ /*
+ * Overruns cause FIFO pointers to become missaligned.
+ * Flushing the receive FIFO reinitializes the pointers.
+ */
+ writeb(UARTCFIFO_RXFLUSH, sport->port.membase + UARTCFIFO);
+ writeb(UARTSFIFO_RXOF, sport->port.membase + UARTSFIFO);
+ }
+
+ uart_unlock_and_check_sysrq(&sport->port);
+
+ tty_flip_buffer_push(port);
+}
+
+static void lpuart32_txint(struct lpuart_port *sport)
+{
+ spin_lock(&sport->port.lock);
+ lpuart32_transmit_buffer(sport);
+ spin_unlock(&sport->port.lock);
+}
+
+static void lpuart32_rxint(struct lpuart_port *sport)
+{
+ unsigned int flg, ignored = 0;
+ struct tty_port *port = &sport->port.state->port;
+ unsigned long rx, sr;
+ bool is_break;
+
+ spin_lock(&sport->port.lock);
+
+ while (!(lpuart32_read(&sport->port, UARTFIFO) & UARTFIFO_RXEMPT)) {
+ flg = TTY_NORMAL;
+ sport->port.icount.rx++;
+ /*
+ * to clear the FE, OR, NF, FE, PE flags,
+ * read STAT then read DATA reg
+ */
+ sr = lpuart32_read(&sport->port, UARTSTAT);
+ rx = lpuart32_read(&sport->port, UARTDATA);
+ rx &= UARTDATA_MASK;
+
+ /*
+ * The LPUART can't distinguish between a break and a framing error,
+ * thus we assume it is a break if the received data is zero.
+ */
+ is_break = (sr & UARTSTAT_FE) && !rx;
+
+ if (is_break && uart_handle_break(&sport->port))
+ continue;
+
+ if (uart_prepare_sysrq_char(&sport->port, rx))
+ continue;
+
+ if (sr & (UARTSTAT_PE | UARTSTAT_OR | UARTSTAT_FE)) {
+ if (sr & UARTSTAT_PE) {
+ sport->port.icount.parity++;
+ } else if (sr & UARTSTAT_FE) {
+ if (is_break)
+ sport->port.icount.brk++;
+ else
+ sport->port.icount.frame++;
+ }
+
+ if (sr & UARTSTAT_OR)
+ sport->port.icount.overrun++;
+
+ if (sr & sport->port.ignore_status_mask) {
+ if (++ignored > 100)
+ goto out;
+ continue;
+ }
+
+ sr &= sport->port.read_status_mask;
+
+ if (sr & UARTSTAT_PE) {
+ flg = TTY_PARITY;
+ } else if (sr & UARTSTAT_FE) {
+ if (is_break)
+ flg = TTY_BREAK;
+ else
+ flg = TTY_FRAME;
+ }
+
+ if (sr & UARTSTAT_OR)
+ flg = TTY_OVERRUN;
+ }
+
+ if (sport->is_cs7)
+ rx &= 0x7F;
+
+ if (tty_insert_flip_char(port, rx, flg) == 0)
+ sport->port.icount.buf_overrun++;
+ }
+
+out:
+ uart_unlock_and_check_sysrq(&sport->port);
+
+ tty_flip_buffer_push(port);
+}
+
+static irqreturn_t lpuart_int(int irq, void *dev_id)
+{
+ struct lpuart_port *sport = dev_id;
+ unsigned char sts;
+
+ sts = readb(sport->port.membase + UARTSR1);
+
+ /* SysRq, using dma, check for linebreak by framing err. */
+ if (sts & UARTSR1_FE && sport->lpuart_dma_rx_use) {
+ readb(sport->port.membase + UARTDR);
+ uart_handle_break(&sport->port);
+ /* linebreak produces some garbage, removing it */
+ writeb(UARTCFIFO_RXFLUSH, sport->port.membase + UARTCFIFO);
+ return IRQ_HANDLED;
+ }
+
+ if (sts & UARTSR1_RDRF && !sport->lpuart_dma_rx_use)
+ lpuart_rxint(sport);
+
+ if (sts & UARTSR1_TDRE && !sport->lpuart_dma_tx_use)
+ lpuart_txint(sport);
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t lpuart32_int(int irq, void *dev_id)
+{
+ struct lpuart_port *sport = dev_id;
+ unsigned long sts, rxcount;
+
+ sts = lpuart32_read(&sport->port, UARTSTAT);
+ rxcount = lpuart32_read(&sport->port, UARTWATER);
+ rxcount = rxcount >> UARTWATER_RXCNT_OFF;
+
+ if ((sts & UARTSTAT_RDRF || rxcount > 0) && !sport->lpuart_dma_rx_use)
+ lpuart32_rxint(sport);
+
+ if ((sts & UARTSTAT_TDRE) && !sport->lpuart_dma_tx_use)
+ lpuart32_txint(sport);
+
+ lpuart32_write(&sport->port, sts, UARTSTAT);
+ return IRQ_HANDLED;
+}
+
+
+static inline void lpuart_handle_sysrq_chars(struct uart_port *port,
+ unsigned char *p, int count)
+{
+ while (count--) {
+ if (*p && uart_handle_sysrq_char(port, *p))
+ return;
+ p++;
+ }
+}
+
+static void lpuart_handle_sysrq(struct lpuart_port *sport)
+{
+ struct circ_buf *ring = &sport->rx_ring;
+ int count;
+
+ if (ring->head < ring->tail) {
+ count = sport->rx_sgl.length - ring->tail;
+ lpuart_handle_sysrq_chars(&sport->port,
+ ring->buf + ring->tail, count);
+ ring->tail = 0;
+ }
+
+ if (ring->head > ring->tail) {
+ count = ring->head - ring->tail;
+ lpuart_handle_sysrq_chars(&sport->port,
+ ring->buf + ring->tail, count);
+ ring->tail = ring->head;
+ }
+}
+
+static int lpuart_tty_insert_flip_string(struct tty_port *port,
+ unsigned char *chars, size_t size, bool is_cs7)
+{
+ int i;
+
+ if (is_cs7)
+ for (i = 0; i < size; i++)
+ chars[i] &= 0x7F;
+ return tty_insert_flip_string(port, chars, size);
+}
+
+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 dma_chan *chan = sport->dma_rx_chan;
+ struct circ_buf *ring = &sport->rx_ring;
+ unsigned long flags;
+ int count, copied;
+
+ if (lpuart_is_32(sport)) {
+ unsigned long sr = lpuart32_read(&sport->port, UARTSTAT);
+
+ if (sr & (UARTSTAT_PE | UARTSTAT_FE)) {
+ /* Clear the error flags */
+ lpuart32_write(&sport->port, sr, UARTSTAT);
+
+ if (sr & UARTSTAT_PE)
+ sport->port.icount.parity++;
+ else if (sr & UARTSTAT_FE)
+ sport->port.icount.frame++;
+ }
+ } else {
+ unsigned char sr = readb(sport->port.membase + UARTSR1);
+
+ if (sr & (UARTSR1_PE | UARTSR1_FE)) {
+ unsigned char cr2;
+
+ /* Disable receiver during this operation... */
+ cr2 = readb(sport->port.membase + UARTCR2);
+ cr2 &= ~UARTCR2_RE;
+ writeb(cr2, sport->port.membase + UARTCR2);
+
+ /* Read DR to clear the error flags */
+ readb(sport->port.membase + UARTDR);
+
+ if (sr & UARTSR1_PE)
+ sport->port.icount.parity++;
+ else if (sr & UARTSR1_FE)
+ sport->port.icount.frame++;
+ /*
+ * At this point parity/framing error is
+ * cleared However, since the DMA already read
+ * the data register and we had to read it
+ * again after reading the status register to
+ * properly clear the flags, the FIFO actually
+ * underflowed... This requires a clearing of
+ * the FIFO...
+ */
+ if (readb(sport->port.membase + UARTSFIFO) &
+ UARTSFIFO_RXUF) {
+ writeb(UARTSFIFO_RXUF,
+ sport->port.membase + UARTSFIFO);
+ writeb(UARTCFIFO_RXFLUSH,
+ sport->port.membase + UARTCFIFO);
+ }
+
+ cr2 |= UARTCR2_RE;
+ writeb(cr2, sport->port.membase + UARTCR2);
+ }
+ }
+
+ async_tx_ack(sport->dma_rx_desc);
+
+ spin_lock_irqsave(&sport->port.lock, flags);
+
+ dmastat = dmaengine_tx_status(chan, sport->dma_rx_cookie, &state);
+ if (dmastat == DMA_ERROR) {
+ dev_err(sport->port.dev, "Rx DMA transfer failed!\n");
+ spin_unlock_irqrestore(&sport->port.lock, flags);
+ return;
+ }
+
+ /* CPU claims ownership of RX DMA buffer */
+ dma_sync_sg_for_cpu(chan->device->dev, &sport->rx_sgl, 1,
+ DMA_FROM_DEVICE);
+
+ /*
+ * ring->head points to the end of data already written by the DMA.
+ * ring->tail points to the beginning of data to be read by the
+ * framework.
+ * The current transfer size should not be larger than the dma buffer
+ * length.
+ */
+ ring->head = sport->rx_sgl.length - state.residue;
+ BUG_ON(ring->head > sport->rx_sgl.length);
+
+ /*
+ * Silent handling of keys pressed in the sysrq timeframe
+ */
+ if (sport->port.sysrq) {
+ lpuart_handle_sysrq(sport);
+ goto exit;
+ }
+
+ /*
+ * At this point ring->head may point to the first byte right after the
+ * last byte of the dma buffer:
+ * 0 <= ring->head <= sport->rx_sgl.length
+ *
+ * However ring->tail must always points inside the dma buffer:
+ * 0 <= ring->tail <= sport->rx_sgl.length - 1
+ *
+ * Since we use a ring buffer, we have to handle the case
+ * where head is lower than tail. In such a case, we first read from
+ * tail to the end of the buffer then reset tail.
+ */
+ if (ring->head < ring->tail) {
+ count = sport->rx_sgl.length - ring->tail;
+
+ copied = lpuart_tty_insert_flip_string(port, ring->buf + ring->tail,
+ count, sport->is_cs7);
+ if (copied != count)
+ sport->port.icount.buf_overrun++;
+ ring->tail = 0;
+ sport->port.icount.rx += copied;
+ }
+
+ /* Finally we read data from tail to head */
+ if (ring->tail < ring->head) {
+ count = ring->head - ring->tail;
+ copied = lpuart_tty_insert_flip_string(port, ring->buf + ring->tail,
+ count, sport->is_cs7);
+ if (copied != count)
+ sport->port.icount.buf_overrun++;
+ /* Wrap ring->head if needed */
+ if (ring->head >= sport->rx_sgl.length)
+ ring->head = 0;
+ ring->tail = ring->head;
+ sport->port.icount.rx += copied;
+ }
+
+exit:
+ dma_sync_sg_for_device(chan->device->dev, &sport->rx_sgl, 1,
+ DMA_FROM_DEVICE);
+
+ spin_unlock_irqrestore(&sport->port.lock, flags);
+
+ tty_flip_buffer_push(port);
+ mod_timer(&sport->lpuart_timer, jiffies + sport->dma_rx_timeout);
+}
+
+static void lpuart_dma_rx_complete(void *arg)
+{
+ struct lpuart_port *sport = arg;
+
+ lpuart_copy_rx_to_tty(sport);
+}
+
+static void lpuart_timer_func(struct timer_list *t)
+{
+ struct lpuart_port *sport = from_timer(sport, t, lpuart_timer);
+
+ lpuart_copy_rx_to_tty(sport);
+}
+
+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;
+ struct tty_port *port = &sport->port.state->port;
+ struct tty_struct *tty = port->tty;
+ struct ktermios *termios = &tty->termios;
+ struct dma_chan *chan = sport->dma_rx_chan;
+ unsigned int bits = tty_get_frame_size(termios->c_cflag);
+ unsigned int baud = tty_get_baud_rate(tty);
+
+ /*
+ * Calculate length of one DMA buffer size to keep latency below
+ * 10ms at any baud rate.
+ */
+ sport->rx_dma_rng_buf_len = (DMA_RX_TIMEOUT * baud / bits / 1000) * 2;
+ sport->rx_dma_rng_buf_len = (1 << fls(sport->rx_dma_rng_buf_len));
+ if (sport->rx_dma_rng_buf_len < 16)
+ sport->rx_dma_rng_buf_len = 16;
+
+ ring->buf = kzalloc(sport->rx_dma_rng_buf_len, GFP_ATOMIC);
+ if (!ring->buf)
+ return -ENOMEM;
+
+ sg_init_one(&sport->rx_sgl, ring->buf, sport->rx_dma_rng_buf_len);
+ nent = dma_map_sg(chan->device->dev, &sport->rx_sgl, 1,
+ DMA_FROM_DEVICE);
+
+ if (!nent) {
+ dev_err(sport->port.dev, "DMA Rx mapping error\n");
+ return -EINVAL;
+ }
+
+ dma_rx_sconfig.src_addr = lpuart_dma_datareg_addr(sport);
+ dma_rx_sconfig.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+ dma_rx_sconfig.src_maxburst = 1;
+ dma_rx_sconfig.direction = DMA_DEV_TO_MEM;
+ ret = dmaengine_slave_config(chan, &dma_rx_sconfig);
+
+ if (ret < 0) {
+ dev_err(sport->port.dev,
+ "DMA Rx slave config failed, err = %d\n", ret);
+ return ret;
+ }
+
+ sport->dma_rx_desc = dmaengine_prep_dma_cyclic(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(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;
+}
+
+static void lpuart_dma_rx_free(struct uart_port *port)
+{
+ struct lpuart_port *sport = container_of(port,
+ struct lpuart_port, port);
+ struct dma_chan *chan = sport->dma_rx_chan;
+
+ dmaengine_terminate_sync(chan);
+ del_timer_sync(&sport->lpuart_timer);
+ dma_unmap_sg(chan->device->dev, &sport->rx_sgl, 1, DMA_FROM_DEVICE);
+ kfree(sport->rx_ring.buf);
+ sport->rx_ring.tail = 0;
+ sport->rx_ring.head = 0;
+ sport->dma_rx_desc = NULL;
+ sport->dma_rx_cookie = -EINVAL;
+}
+
+static int lpuart_config_rs485(struct uart_port *port, struct ktermios *termios,
+ struct serial_rs485 *rs485)
+{
+ struct lpuart_port *sport = container_of(port,
+ struct lpuart_port, port);
+
+ u8 modem = readb(sport->port.membase + UARTMODEM) &
+ ~(UARTMODEM_TXRTSPOL | UARTMODEM_TXRTSE);
+ writeb(modem, sport->port.membase + UARTMODEM);
+
+ if (rs485->flags & SER_RS485_ENABLED) {
+ /* Enable auto RS-485 RTS mode */
+ modem |= UARTMODEM_TXRTSE;
+
+ /*
+ * The hardware defaults to RTS logic HIGH while transfer.
+ * Switch polarity in case RTS shall be logic HIGH
+ * after transfer.
+ * Note: UART is assumed to be active high.
+ */
+ if (rs485->flags & SER_RS485_RTS_ON_SEND)
+ modem |= UARTMODEM_TXRTSPOL;
+ else if (rs485->flags & SER_RS485_RTS_AFTER_SEND)
+ modem &= ~UARTMODEM_TXRTSPOL;
+ }
+
+ writeb(modem, sport->port.membase + UARTMODEM);
+ return 0;
+}
+
+static int lpuart32_config_rs485(struct uart_port *port, struct ktermios *termios,
+ struct serial_rs485 *rs485)
+{
+ struct lpuart_port *sport = container_of(port,
+ struct lpuart_port, port);
+
+ unsigned long modem = lpuart32_read(&sport->port, UARTMODIR)
+ & ~(UARTMODEM_TXRTSPOL | UARTMODEM_TXRTSE);
+ lpuart32_write(&sport->port, modem, UARTMODIR);
+
+ if (rs485->flags & SER_RS485_ENABLED) {
+ /* Enable auto RS-485 RTS mode */
+ modem |= UARTMODEM_TXRTSE;
+
+ /*
+ * The hardware defaults to RTS logic HIGH while transfer.
+ * Switch polarity in case RTS shall be logic HIGH
+ * after transfer.
+ * Note: UART is assumed to be active high.
+ */
+ if (rs485->flags & SER_RS485_RTS_ON_SEND)
+ modem |= UARTMODEM_TXRTSPOL;
+ else if (rs485->flags & SER_RS485_RTS_AFTER_SEND)
+ modem &= ~UARTMODEM_TXRTSPOL;
+ }
+
+ lpuart32_write(&sport->port, modem, UARTMODIR);
+ return 0;
+}
+
+static unsigned int lpuart_get_mctrl(struct uart_port *port)
+{
+ unsigned int mctrl = 0;
+ u8 reg;
+
+ reg = readb(port->membase + UARTCR1);
+ if (reg & UARTCR1_LOOPS)
+ mctrl |= TIOCM_LOOP;
+
+ return mctrl;
+}
+
+static unsigned int lpuart32_get_mctrl(struct uart_port *port)
+{
+ unsigned int mctrl = TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
+ u32 reg;
+
+ reg = lpuart32_read(port, UARTCTRL);
+ if (reg & UARTCTRL_LOOPS)
+ mctrl |= TIOCM_LOOP;
+
+ return mctrl;
+}
+
+static void lpuart_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+ u8 reg;
+
+ reg = readb(port->membase + UARTCR1);
+
+ /* for internal loopback we need LOOPS=1 and RSRC=0 */
+ reg &= ~(UARTCR1_LOOPS | UARTCR1_RSRC);
+ if (mctrl & TIOCM_LOOP)
+ reg |= UARTCR1_LOOPS;
+
+ writeb(reg, port->membase + UARTCR1);
+}
+
+static void lpuart32_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+ u32 reg;
+
+ reg = lpuart32_read(port, UARTCTRL);
+
+ /* for internal loopback we need LOOPS=1 and RSRC=0 */
+ reg &= ~(UARTCTRL_LOOPS | UARTCTRL_RSRC);
+ if (mctrl & TIOCM_LOOP)
+ reg |= UARTCTRL_LOOPS;
+
+ lpuart32_write(port, reg, UARTCTRL);
+}
+
+static void lpuart_break_ctl(struct uart_port *port, int break_state)
+{
+ unsigned char temp;
+
+ temp = readb(port->membase + UARTCR2) & ~UARTCR2_SBK;
+
+ if (break_state != 0)
+ temp |= UARTCR2_SBK;
+
+ writeb(temp, port->membase + UARTCR2);
+}
+
+static void lpuart32_break_ctl(struct uart_port *port, int break_state)
+{
+ unsigned long temp;
+
+ temp = lpuart32_read(port, UARTCTRL);
+
+ /*
+ * LPUART IP now has two known bugs, one is CTS has higher priority than the
+ * break signal, which causes the break signal sending through UARTCTRL_SBK
+ * may impacted by the CTS input if the HW flow control is enabled. It
+ * exists on all platforms we support in this driver.
+ * Another bug is i.MX8QM LPUART may have an additional break character
+ * being sent after SBK was cleared.
+ * To avoid above two bugs, we use Transmit Data Inversion function to send
+ * the break signal instead of UARTCTRL_SBK.
+ */
+ if (break_state != 0) {
+ /*
+ * Disable the transmitter to prevent any data from being sent out
+ * during break, then invert the TX line to send break.
+ */
+ temp &= ~UARTCTRL_TE;
+ lpuart32_write(port, temp, UARTCTRL);
+ temp |= UARTCTRL_TXINV;
+ lpuart32_write(port, temp, UARTCTRL);
+ } else {
+ /* Disable the TXINV to turn off break and re-enable transmitter. */
+ temp &= ~UARTCTRL_TXINV;
+ lpuart32_write(port, temp, UARTCTRL);
+ temp |= UARTCTRL_TE;
+ lpuart32_write(port, temp, UARTCTRL);
+ }
+}
+
+static void lpuart_setup_watermark(struct lpuart_port *sport)
+{
+ unsigned char val, cr2;
+ unsigned char cr2_saved;
+
+ cr2 = readb(sport->port.membase + UARTCR2);
+ cr2_saved = cr2;
+ cr2 &= ~(UARTCR2_TIE | UARTCR2_TCIE | UARTCR2_TE |
+ UARTCR2_RIE | UARTCR2_RE);
+ writeb(cr2, sport->port.membase + UARTCR2);
+
+ val = readb(sport->port.membase + UARTPFIFO);
+ writeb(val | UARTPFIFO_TXFE | UARTPFIFO_RXFE,
+ sport->port.membase + UARTPFIFO);
+
+ /* flush Tx and Rx FIFO */
+ writeb(UARTCFIFO_TXFLUSH | UARTCFIFO_RXFLUSH,
+ sport->port.membase + UARTCFIFO);
+
+ /* explicitly clear RDRF */
+ if (readb(sport->port.membase + UARTSR1) & UARTSR1_RDRF) {
+ readb(sport->port.membase + UARTDR);
+ writeb(UARTSFIFO_RXUF, sport->port.membase + UARTSFIFO);
+ }
+
+ writeb(0, sport->port.membase + UARTTWFIFO);
+ writeb(sport->rx_watermark, sport->port.membase + UARTRWFIFO);
+
+ /* Restore cr2 */
+ writeb(cr2_saved, sport->port.membase + UARTCR2);
+}
+
+static void lpuart_setup_watermark_enable(struct lpuart_port *sport)
+{
+ unsigned char cr2;
+
+ lpuart_setup_watermark(sport);
+
+ cr2 = readb(sport->port.membase + UARTCR2);
+ cr2 |= UARTCR2_RIE | UARTCR2_RE | UARTCR2_TE;
+ writeb(cr2, sport->port.membase + UARTCR2);
+}
+
+static void lpuart32_setup_watermark(struct lpuart_port *sport)
+{
+ unsigned long val, ctrl;
+ unsigned long ctrl_saved;
+
+ ctrl = lpuart32_read(&sport->port, UARTCTRL);
+ ctrl_saved = ctrl;
+ ctrl &= ~(UARTCTRL_TIE | UARTCTRL_TCIE | UARTCTRL_TE |
+ UARTCTRL_RIE | UARTCTRL_RE);
+ lpuart32_write(&sport->port, ctrl, UARTCTRL);
+
+ /* enable FIFO mode */
+ val = lpuart32_read(&sport->port, UARTFIFO);
+ val |= UARTFIFO_TXFE | UARTFIFO_RXFE;
+ val |= UARTFIFO_TXFLUSH | UARTFIFO_RXFLUSH;
+ lpuart32_write(&sport->port, val, UARTFIFO);
+
+ /* set the watermark */
+ val = (sport->rx_watermark << UARTWATER_RXWATER_OFF) |
+ (0x0 << UARTWATER_TXWATER_OFF);
+ lpuart32_write(&sport->port, val, UARTWATER);
+
+ /* Restore cr2 */
+ lpuart32_write(&sport->port, ctrl_saved, UARTCTRL);
+}
+
+static void lpuart32_setup_watermark_enable(struct lpuart_port *sport)
+{
+ u32 temp;
+
+ lpuart32_setup_watermark(sport);
+
+ temp = lpuart32_read(&sport->port, UARTCTRL);
+ temp |= UARTCTRL_RE | UARTCTRL_TE | UARTCTRL_ILIE;
+ lpuart32_write(&sport->port, temp, UARTCTRL);
+}
+
+static void rx_dma_timer_init(struct lpuart_port *sport)
+{
+ 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_request_dma(struct lpuart_port *sport)
+{
+ sport->dma_tx_chan = dma_request_chan(sport->port.dev, "tx");
+ if (IS_ERR(sport->dma_tx_chan)) {
+ dev_dbg_once(sport->port.dev,
+ "DMA tx channel request failed, operating without tx DMA (%ld)\n",
+ PTR_ERR(sport->dma_tx_chan));
+ sport->dma_tx_chan = NULL;
+ }
+
+ sport->dma_rx_chan = dma_request_chan(sport->port.dev, "rx");
+ if (IS_ERR(sport->dma_rx_chan)) {
+ dev_dbg_once(sport->port.dev,
+ "DMA rx channel request failed, operating without rx DMA (%ld)\n",
+ PTR_ERR(sport->dma_rx_chan));
+ sport->dma_rx_chan = NULL;
+ }
+}
+
+static void lpuart_tx_dma_startup(struct lpuart_port *sport)
+{
+ u32 uartbaud;
+ int ret;
+
+ if (uart_console(&sport->port))
+ goto err;
+
+ if (!sport->dma_tx_chan)
+ goto err;
+
+ ret = lpuart_dma_tx_request(&sport->port);
+ if (ret)
+ goto err;
+
+ init_waitqueue_head(&sport->dma_wait);
+ sport->lpuart_dma_tx_use = true;
+ if (lpuart_is_32(sport)) {
+ uartbaud = lpuart32_read(&sport->port, UARTBAUD);
+ lpuart32_write(&sport->port,
+ uartbaud | UARTBAUD_TDMAE, UARTBAUD);
+ } else {
+ writeb(readb(sport->port.membase + UARTCR5) |
+ UARTCR5_TDMAS, sport->port.membase + UARTCR5);
+ }
+
+ return;
+
+err:
+ sport->lpuart_dma_tx_use = false;
+}
+
+static void lpuart_rx_dma_startup(struct lpuart_port *sport)
+{
+ int ret;
+ unsigned char cr3;
+
+ if (uart_console(&sport->port))
+ goto err;
+
+ if (!sport->dma_rx_chan)
+ goto err;
+
+ ret = lpuart_start_rx_dma(sport);
+ if (ret)
+ goto err;
+
+ /* set Rx DMA timeout */
+ sport->dma_rx_timeout = msecs_to_jiffies(DMA_RX_TIMEOUT);
+ if (!sport->dma_rx_timeout)
+ sport->dma_rx_timeout = 1;
+
+ sport->lpuart_dma_rx_use = true;
+ rx_dma_timer_init(sport);
+
+ if (sport->port.has_sysrq && !lpuart_is_32(sport)) {
+ cr3 = readb(sport->port.membase + UARTCR3);
+ cr3 |= UARTCR3_FEIE;
+ writeb(cr3, sport->port.membase + UARTCR3);
+ }
+
+ return;
+
+err:
+ sport->lpuart_dma_rx_use = false;
+}
+
+static int lpuart_startup(struct uart_port *port)
+{
+ struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
+ unsigned long flags;
+ unsigned char temp;
+
+ /* determine FIFO size and enable FIFO mode */
+ temp = readb(sport->port.membase + UARTPFIFO);
+
+ sport->txfifo_size = UARTFIFO_DEPTH((temp >> UARTPFIFO_TXSIZE_OFF) &
+ UARTPFIFO_FIFOSIZE_MASK);
+ sport->port.fifosize = sport->txfifo_size;
+
+ sport->rxfifo_size = UARTFIFO_DEPTH((temp >> UARTPFIFO_RXSIZE_OFF) &
+ UARTPFIFO_FIFOSIZE_MASK);
+
+ lpuart_request_dma(sport);
+
+ spin_lock_irqsave(&sport->port.lock, flags);
+
+ lpuart_setup_watermark_enable(sport);
+
+ lpuart_rx_dma_startup(sport);
+ lpuart_tx_dma_startup(sport);
+
+ spin_unlock_irqrestore(&sport->port.lock, flags);
+
+ return 0;
+}
+
+static void lpuart32_configure(struct lpuart_port *sport)
+{
+ unsigned long temp;
+
+ temp = lpuart32_read(&sport->port, UARTCTRL);
+ if (!sport->lpuart_dma_rx_use)
+ temp |= UARTCTRL_RIE;
+ if (!sport->lpuart_dma_tx_use)
+ temp |= UARTCTRL_TIE;
+ lpuart32_write(&sport->port, temp, UARTCTRL);
+}
+
+static int lpuart32_startup(struct uart_port *port)
+{
+ struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
+ unsigned long flags;
+ unsigned long temp;
+
+ /* determine FIFO size */
+ temp = lpuart32_read(&sport->port, UARTFIFO);
+
+ sport->txfifo_size = UARTFIFO_DEPTH((temp >> UARTFIFO_TXSIZE_OFF) &
+ UARTFIFO_FIFOSIZE_MASK);
+ sport->port.fifosize = sport->txfifo_size;
+
+ sport->rxfifo_size = UARTFIFO_DEPTH((temp >> UARTFIFO_RXSIZE_OFF) &
+ UARTFIFO_FIFOSIZE_MASK);
+
+ /*
+ * The LS1021A and LS1028A have a fixed FIFO depth of 16 words.
+ * Although they support the RX/TXSIZE fields, their encoding is
+ * different. Eg the reference manual states 0b101 is 16 words.
+ */
+ if (is_layerscape_lpuart(sport)) {
+ sport->rxfifo_size = 16;
+ sport->txfifo_size = 16;
+ sport->port.fifosize = sport->txfifo_size;
+ }
+
+ lpuart_request_dma(sport);
+
+ spin_lock_irqsave(&sport->port.lock, flags);
+
+ lpuart32_setup_watermark_enable(sport);
+
+ lpuart_rx_dma_startup(sport);
+ lpuart_tx_dma_startup(sport);
+
+ lpuart32_configure(sport);
+
+ spin_unlock_irqrestore(&sport->port.lock, flags);
+ return 0;
+}
+
+static void lpuart_dma_shutdown(struct lpuart_port *sport)
+{
+ if (sport->lpuart_dma_rx_use) {
+ lpuart_dma_rx_free(&sport->port);
+ sport->lpuart_dma_rx_use = false;
+ }
+
+ if (sport->lpuart_dma_tx_use) {
+ if (wait_event_interruptible_timeout(sport->dma_wait,
+ !sport->dma_tx_in_progress, msecs_to_jiffies(300)) <= 0) {
+ sport->dma_tx_in_progress = false;
+ dmaengine_terminate_sync(sport->dma_tx_chan);
+ }
+ sport->lpuart_dma_tx_use = false;
+ }
+
+ if (sport->dma_tx_chan)
+ dma_release_channel(sport->dma_tx_chan);
+ if (sport->dma_rx_chan)
+ dma_release_channel(sport->dma_rx_chan);
+}
+
+static void lpuart_shutdown(struct uart_port *port)
+{
+ struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
+ unsigned char temp;
+ unsigned long flags;
+
+ spin_lock_irqsave(&port->lock, flags);
+
+ /* disable Rx/Tx and interrupts */
+ temp = readb(port->membase + UARTCR2);
+ temp &= ~(UARTCR2_TE | UARTCR2_RE |
+ UARTCR2_TIE | UARTCR2_TCIE | UARTCR2_RIE);
+ writeb(temp, port->membase + UARTCR2);
+
+ spin_unlock_irqrestore(&port->lock, flags);
+
+ lpuart_dma_shutdown(sport);
+}
+
+static void lpuart32_shutdown(struct uart_port *port)
+{
+ struct lpuart_port *sport =
+ container_of(port, struct lpuart_port, port);
+ unsigned long temp;
+ unsigned long flags;
+
+ spin_lock_irqsave(&port->lock, flags);
+
+ /* clear status */
+ 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);
+ 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);
+ lpuart32_write(port, temp, UARTCTRL);
+
+ spin_unlock_irqrestore(&port->lock, flags);
+
+ lpuart_dma_shutdown(sport);
+}
+
+static void
+lpuart_set_termios(struct uart_port *port, struct ktermios *termios,
+ const struct ktermios *old)
+{
+ struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
+ unsigned long flags;
+ unsigned char cr1, old_cr1, old_cr2, cr3, cr4, bdh, modem;
+ unsigned int baud;
+ unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8;
+ unsigned int sbr, brfa;
+
+ cr1 = old_cr1 = readb(sport->port.membase + UARTCR1);
+ old_cr2 = readb(sport->port.membase + UARTCR2);
+ cr3 = readb(sport->port.membase + UARTCR3);
+ cr4 = readb(sport->port.membase + UARTCR4);
+ bdh = readb(sport->port.membase + UARTBDH);
+ modem = readb(sport->port.membase + UARTMODEM);
+ /*
+ * only support CS8 and CS7, and for CS7 must enable PE.
+ * supported mode:
+ * - (7,e/o,1)
+ * - (8,n,1)
+ * - (8,m/s,1)
+ * - (8,e/o,1)
+ */
+ while ((termios->c_cflag & CSIZE) != CS8 &&
+ (termios->c_cflag & CSIZE) != CS7) {
+ termios->c_cflag &= ~CSIZE;
+ termios->c_cflag |= old_csize;
+ old_csize = CS8;
+ }
+
+ if ((termios->c_cflag & CSIZE) == CS8 ||
+ (termios->c_cflag & CSIZE) == CS7)
+ cr1 = old_cr1 & ~UARTCR1_M;
+
+ if (termios->c_cflag & CMSPAR) {
+ if ((termios->c_cflag & CSIZE) != CS8) {
+ termios->c_cflag &= ~CSIZE;
+ termios->c_cflag |= CS8;
+ }
+ cr1 |= UARTCR1_M;
+ }
+
+ /*
+ * When auto RS-485 RTS mode is enabled,
+ * hardware flow control need to be disabled.
+ */
+ if (sport->port.rs485.flags & SER_RS485_ENABLED)
+ termios->c_cflag &= ~CRTSCTS;
+
+ if (termios->c_cflag & CRTSCTS)
+ modem |= UARTMODEM_RXRTSE | UARTMODEM_TXCTSE;
+ else
+ modem &= ~(UARTMODEM_RXRTSE | UARTMODEM_TXCTSE);
+
+ termios->c_cflag &= ~CSTOPB;
+
+ /* parity must be enabled when CS7 to match 8-bits format */
+ if ((termios->c_cflag & CSIZE) == CS7)
+ termios->c_cflag |= PARENB;
+
+ if (termios->c_cflag & PARENB) {
+ if (termios->c_cflag & CMSPAR) {
+ cr1 &= ~UARTCR1_PE;
+ if (termios->c_cflag & PARODD)
+ cr3 |= UARTCR3_T8;
+ else
+ cr3 &= ~UARTCR3_T8;
+ } else {
+ cr1 |= UARTCR1_PE;
+ if ((termios->c_cflag & CSIZE) == CS8)
+ cr1 |= UARTCR1_M;
+ if (termios->c_cflag & PARODD)
+ cr1 |= UARTCR1_PT;
+ else
+ cr1 &= ~UARTCR1_PT;
+ }
+ } else {
+ cr1 &= ~UARTCR1_PE;
+ }
+
+ /* ask the core to calculate the divisor */
+ baud = uart_get_baud_rate(port, termios, old, 50, port->uartclk / 16);
+
+ /*
+ * Need to update the Ring buffer length according to the selected
+ * 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.
+ */
+ if (old && sport->lpuart_dma_rx_use)
+ lpuart_dma_rx_free(&sport->port);
+
+ spin_lock_irqsave(&sport->port.lock, flags);
+
+ sport->port.read_status_mask = 0;
+ if (termios->c_iflag & INPCK)
+ sport->port.read_status_mask |= UARTSR1_FE | UARTSR1_PE;
+ if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
+ sport->port.read_status_mask |= UARTSR1_FE;
+
+ /* characters to ignore */
+ sport->port.ignore_status_mask = 0;
+ if (termios->c_iflag & IGNPAR)
+ sport->port.ignore_status_mask |= UARTSR1_PE;
+ if (termios->c_iflag & IGNBRK) {
+ sport->port.ignore_status_mask |= UARTSR1_FE;
+ /*
+ * if we're ignoring parity and break indicators,
+ * ignore overruns too (for real raw support).
+ */
+ if (termios->c_iflag & IGNPAR)
+ sport->port.ignore_status_mask |= UARTSR1_OR;
+ }
+
+ /* update the per-port timeout */
+ uart_update_timeout(port, termios->c_cflag, baud);
+
+ /* wait transmit engin complete */
+ lpuart_wait_bit_set(&sport->port, UARTSR1, UARTSR1_TC);
+
+ /* disable transmit and receive */
+ writeb(old_cr2 & ~(UARTCR2_TE | UARTCR2_RE),
+ sport->port.membase + UARTCR2);
+
+ sbr = sport->port.uartclk / (16 * baud);
+ brfa = ((sport->port.uartclk - (16 * sbr * baud)) * 2) / baud;
+ bdh &= ~UARTBDH_SBR_MASK;
+ bdh |= (sbr >> 8) & 0x1F;
+ cr4 &= ~UARTCR4_BRFA_MASK;
+ brfa &= UARTCR4_BRFA_MASK;
+ writeb(cr4 | brfa, sport->port.membase + UARTCR4);
+ writeb(bdh, sport->port.membase + UARTBDH);
+ writeb(sbr & 0xFF, sport->port.membase + UARTBDL);
+ writeb(cr3, sport->port.membase + UARTCR3);
+ writeb(cr1, sport->port.membase + UARTCR1);
+ writeb(modem, sport->port.membase + UARTMODEM);
+
+ /* restore control register */
+ writeb(old_cr2, sport->port.membase + UARTCR2);
+
+ if (old && sport->lpuart_dma_rx_use) {
+ if (!lpuart_start_rx_dma(sport))
+ rx_dma_timer_init(sport);
+ else
+ sport->lpuart_dma_rx_use = false;
+ }
+
+ spin_unlock_irqrestore(&sport->port.lock, flags);
+}
+
+static void __lpuart32_serial_setbrg(struct uart_port *port,
+ unsigned int baudrate, bool use_rx_dma,
+ bool use_tx_dma)
+{
+ u32 sbr, osr, baud_diff, tmp_osr, tmp_sbr, tmp_diff, tmp;
+ u32 clk = port->uartclk;
+
+ /*
+ * The idea is to use the best OSR (over-sampling rate) possible.
+ * Note, OSR is typically hard-set to 16 in other LPUART instantiations.
+ * Loop to find the best OSR value possible, one that generates minimum
+ * baud_diff iterate through the rest of the supported values of OSR.
+ *
+ * Calculation Formula:
+ * Baud Rate = baud clock / ((OSR+1) × SBR)
+ */
+ baud_diff = baudrate;
+ osr = 0;
+ sbr = 0;
+
+ for (tmp_osr = 4; tmp_osr <= 32; tmp_osr++) {
+ /* calculate the temporary sbr value */
+ tmp_sbr = (clk / (baudrate * tmp_osr));
+ if (tmp_sbr == 0)
+ tmp_sbr = 1;
+
+ /*
+ * calculate the baud rate difference based on the temporary
+ * osr and sbr values
+ */
+ tmp_diff = clk / (tmp_osr * tmp_sbr) - baudrate;
+
+ /* select best values between sbr and sbr+1 */
+ tmp = clk / (tmp_osr * (tmp_sbr + 1));
+ if (tmp_diff > (baudrate - tmp)) {
+ tmp_diff = baudrate - tmp;
+ tmp_sbr++;
+ }
+
+ if (tmp_sbr > UARTBAUD_SBR_MASK)
+ continue;
+
+ if (tmp_diff <= baud_diff) {
+ baud_diff = tmp_diff;
+ osr = tmp_osr;
+ sbr = tmp_sbr;
+
+ if (!baud_diff)
+ break;
+ }
+ }
+
+ /* handle buadrate outside acceptable rate */
+ if (baud_diff > ((baudrate / 100) * 3))
+ dev_warn(port->dev,
+ "unacceptable baud rate difference of more than 3%%\n");
+
+ tmp = lpuart32_read(port, UARTBAUD);
+
+ if ((osr > 3) && (osr < 8))
+ tmp |= UARTBAUD_BOTHEDGE;
+
+ tmp &= ~(UARTBAUD_OSR_MASK << UARTBAUD_OSR_SHIFT);
+ tmp |= ((osr-1) & UARTBAUD_OSR_MASK) << UARTBAUD_OSR_SHIFT;
+
+ tmp &= ~UARTBAUD_SBR_MASK;
+ tmp |= sbr & UARTBAUD_SBR_MASK;
+
+ if (!use_rx_dma)
+ tmp &= ~UARTBAUD_RDMAE;
+ if (!use_tx_dma)
+ tmp &= ~UARTBAUD_TDMAE;
+
+ lpuart32_write(port, tmp, UARTBAUD);
+}
+
+static void lpuart32_serial_setbrg(struct lpuart_port *sport,
+ unsigned int baudrate)
+{
+ __lpuart32_serial_setbrg(&sport->port, baudrate,
+ sport->lpuart_dma_rx_use,
+ sport->lpuart_dma_tx_use);
+}
+
+
+static void
+lpuart32_set_termios(struct uart_port *port, struct ktermios *termios,
+ const struct ktermios *old)
+{
+ struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
+ unsigned long flags;
+ unsigned long ctrl, old_ctrl, bd, modem;
+ unsigned int baud;
+ unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8;
+
+ ctrl = old_ctrl = lpuart32_read(&sport->port, UARTCTRL);
+ bd = lpuart32_read(&sport->port, UARTBAUD);
+ modem = lpuart32_read(&sport->port, UARTMODIR);
+ sport->is_cs7 = false;
+ /*
+ * only support CS8 and CS7, and for CS7 must enable PE.
+ * supported mode:
+ * - (7,e/o,1)
+ * - (8,n,1)
+ * - (8,m/s,1)
+ * - (8,e/o,1)
+ */
+ while ((termios->c_cflag & CSIZE) != CS8 &&
+ (termios->c_cflag & CSIZE) != CS7) {
+ termios->c_cflag &= ~CSIZE;
+ termios->c_cflag |= old_csize;
+ old_csize = CS8;
+ }
+
+ if ((termios->c_cflag & CSIZE) == CS8 ||
+ (termios->c_cflag & CSIZE) == CS7)
+ ctrl = old_ctrl & ~UARTCTRL_M;
+
+ if (termios->c_cflag & CMSPAR) {
+ if ((termios->c_cflag & CSIZE) != CS8) {
+ termios->c_cflag &= ~CSIZE;
+ termios->c_cflag |= CS8;
+ }
+ ctrl |= UARTCTRL_M;
+ }
+
+ /*
+ * When auto RS-485 RTS mode is enabled,
+ * hardware flow control need to be disabled.
+ */
+ if (sport->port.rs485.flags & SER_RS485_ENABLED)
+ termios->c_cflag &= ~CRTSCTS;
+
+ if (termios->c_cflag & CRTSCTS)
+ modem |= UARTMODIR_RXRTSE | UARTMODIR_TXCTSE;
+ else
+ modem &= ~(UARTMODIR_RXRTSE | UARTMODIR_TXCTSE);
+
+ if (termios->c_cflag & CSTOPB)
+ bd |= UARTBAUD_SBNS;
+ else
+ bd &= ~UARTBAUD_SBNS;
+
+ /* parity must be enabled when CS7 to match 8-bits format */
+ if ((termios->c_cflag & CSIZE) == CS7)
+ termios->c_cflag |= PARENB;
+
+ if ((termios->c_cflag & PARENB)) {
+ if (termios->c_cflag & CMSPAR) {
+ ctrl &= ~UARTCTRL_PE;
+ ctrl |= UARTCTRL_M;
+ } else {
+ ctrl |= UARTCTRL_PE;
+ if ((termios->c_cflag & CSIZE) == CS8)
+ ctrl |= UARTCTRL_M;
+ if (termios->c_cflag & PARODD)
+ ctrl |= UARTCTRL_PT;
+ else
+ ctrl &= ~UARTCTRL_PT;
+ }
+ } else {
+ ctrl &= ~UARTCTRL_PE;
+ }
+
+ /* ask the core to calculate the divisor */
+ baud = uart_get_baud_rate(port, termios, old, 50, port->uartclk / 4);
+
+ /*
+ * Need to update the Ring buffer length according to the selected
+ * 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.
+ */
+ if (old && sport->lpuart_dma_rx_use)
+ lpuart_dma_rx_free(&sport->port);
+
+ spin_lock_irqsave(&sport->port.lock, flags);
+
+ sport->port.read_status_mask = 0;
+ if (termios->c_iflag & INPCK)
+ sport->port.read_status_mask |= UARTSTAT_FE | UARTSTAT_PE;
+ if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
+ sport->port.read_status_mask |= UARTSTAT_FE;
+
+ /* characters to ignore */
+ sport->port.ignore_status_mask = 0;
+ if (termios->c_iflag & IGNPAR)
+ sport->port.ignore_status_mask |= UARTSTAT_PE;
+ if (termios->c_iflag & IGNBRK) {
+ sport->port.ignore_status_mask |= UARTSTAT_FE;
+ /*
+ * if we're ignoring parity and break indicators,
+ * ignore overruns too (for real raw support).
+ */
+ if (termios->c_iflag & IGNPAR)
+ sport->port.ignore_status_mask |= UARTSTAT_OR;
+ }
+
+ /* update the per-port timeout */
+ uart_update_timeout(port, termios->c_cflag, baud);
+
+ /*
+ * LPUART Transmission Complete Flag may never be set while queuing a break
+ * character, so skip waiting for transmission complete when UARTCTRL_SBK is
+ * asserted.
+ */
+ if (!(old_ctrl & UARTCTRL_SBK)) {
+ lpuart32_write(&sport->port, 0, UARTMODIR);
+ lpuart32_wait_bit_set(&sport->port, UARTSTAT, UARTSTAT_TC);
+ }
+
+ /* disable transmit and receive */
+ lpuart32_write(&sport->port, old_ctrl & ~(UARTCTRL_TE | UARTCTRL_RE),
+ UARTCTRL);
+
+ lpuart32_write(&sport->port, bd, UARTBAUD);
+ lpuart32_serial_setbrg(sport, baud);
+ lpuart32_write(&sport->port, modem, UARTMODIR);
+ lpuart32_write(&sport->port, ctrl, UARTCTRL);
+ /* restore control register */
+
+ if ((ctrl & (UARTCTRL_PE | UARTCTRL_M)) == UARTCTRL_PE)
+ sport->is_cs7 = true;
+
+ if (old && sport->lpuart_dma_rx_use) {
+ if (!lpuart_start_rx_dma(sport))
+ rx_dma_timer_init(sport);
+ else
+ sport->lpuart_dma_rx_use = false;
+ }
+
+ spin_unlock_irqrestore(&sport->port.lock, flags);
+}
+
+static const char *lpuart_type(struct uart_port *port)
+{
+ return "FSL_LPUART";
+}
+
+static void lpuart_release_port(struct uart_port *port)
+{
+ /* nothing to do */
+}
+
+static int lpuart_request_port(struct uart_port *port)
+{
+ return 0;
+}
+
+/* configure/autoconfigure the port */
+static void lpuart_config_port(struct uart_port *port, int flags)
+{
+ if (flags & UART_CONFIG_TYPE)
+ port->type = PORT_LPUART;
+}
+
+static int lpuart_verify_port(struct uart_port *port, struct serial_struct *ser)
+{
+ int ret = 0;
+
+ if (ser->type != PORT_UNKNOWN && ser->type != PORT_LPUART)
+ ret = -EINVAL;
+ if (port->irq != ser->irq)
+ ret = -EINVAL;
+ if (ser->io_type != UPIO_MEM)
+ ret = -EINVAL;
+ if (port->uartclk / 16 != ser->baud_base)
+ ret = -EINVAL;
+ if (port->iobase != ser->port)
+ ret = -EINVAL;
+ if (ser->hub6 != 0)
+ ret = -EINVAL;
+ return ret;
+}
+
+static const struct uart_ops lpuart_pops = {
+ .tx_empty = lpuart_tx_empty,
+ .set_mctrl = lpuart_set_mctrl,
+ .get_mctrl = lpuart_get_mctrl,
+ .stop_tx = lpuart_stop_tx,
+ .start_tx = lpuart_start_tx,
+ .stop_rx = lpuart_stop_rx,
+ .break_ctl = lpuart_break_ctl,
+ .startup = lpuart_startup,
+ .shutdown = lpuart_shutdown,
+ .set_termios = lpuart_set_termios,
+ .type = lpuart_type,
+ .request_port = lpuart_request_port,
+ .release_port = lpuart_release_port,
+ .config_port = lpuart_config_port,
+ .verify_port = lpuart_verify_port,
+ .flush_buffer = lpuart_flush_buffer,
+#if defined(CONFIG_CONSOLE_POLL)
+ .poll_init = lpuart_poll_init,
+ .poll_get_char = lpuart_poll_get_char,
+ .poll_put_char = lpuart_poll_put_char,
+#endif
+};
+
+static const struct uart_ops lpuart32_pops = {
+ .tx_empty = lpuart32_tx_empty,
+ .set_mctrl = lpuart32_set_mctrl,
+ .get_mctrl = lpuart32_get_mctrl,
+ .stop_tx = lpuart32_stop_tx,
+ .start_tx = lpuart32_start_tx,
+ .stop_rx = lpuart32_stop_rx,
+ .break_ctl = lpuart32_break_ctl,
+ .startup = lpuart32_startup,
+ .shutdown = lpuart32_shutdown,
+ .set_termios = lpuart32_set_termios,
+ .type = lpuart_type,
+ .request_port = lpuart_request_port,
+ .release_port = lpuart_release_port,
+ .config_port = lpuart_config_port,
+ .verify_port = lpuart_verify_port,
+ .flush_buffer = lpuart_flush_buffer,
+#if defined(CONFIG_CONSOLE_POLL)
+ .poll_init = lpuart32_poll_init,
+ .poll_get_char = lpuart32_poll_get_char,
+ .poll_put_char = lpuart32_poll_put_char,
+#endif
+};
+
+static struct lpuart_port *lpuart_ports[UART_NR];
+
+#ifdef CONFIG_SERIAL_FSL_LPUART_CONSOLE
+static void lpuart_console_putchar(struct uart_port *port, unsigned char ch)
+{
+ lpuart_wait_bit_set(port, UARTSR1, UARTSR1_TDRE);
+ writeb(ch, port->membase + UARTDR);
+}
+
+static void lpuart32_console_putchar(struct uart_port *port, unsigned char ch)
+{
+ lpuart32_wait_bit_set(port, UARTSTAT, UARTSTAT_TDRE);
+ lpuart32_write(port, ch, UARTDATA);
+}
+
+static void
+lpuart_console_write(struct console *co, const char *s, unsigned int count)
+{
+ struct lpuart_port *sport = lpuart_ports[co->index];
+ unsigned char old_cr2, cr2;
+ unsigned long flags;
+ int locked = 1;
+
+ if (oops_in_progress)
+ locked = spin_trylock_irqsave(&sport->port.lock, flags);
+ else
+ spin_lock_irqsave(&sport->port.lock, flags);
+
+ /* first save CR2 and then disable interrupts */
+ cr2 = old_cr2 = readb(sport->port.membase + UARTCR2);
+ cr2 |= UARTCR2_TE | UARTCR2_RE;
+ cr2 &= ~(UARTCR2_TIE | UARTCR2_TCIE | UARTCR2_RIE);
+ writeb(cr2, sport->port.membase + UARTCR2);
+
+ uart_console_write(&sport->port, s, count, lpuart_console_putchar);
+
+ /* wait for transmitter finish complete and restore CR2 */
+ lpuart_wait_bit_set(&sport->port, UARTSR1, UARTSR1_TC);
+
+ writeb(old_cr2, sport->port.membase + UARTCR2);
+
+ if (locked)
+ spin_unlock_irqrestore(&sport->port.lock, flags);
+}
+
+static void
+lpuart32_console_write(struct console *co, const char *s, unsigned int count)
+{
+ struct lpuart_port *sport = lpuart_ports[co->index];
+ unsigned long old_cr, cr;
+ unsigned long flags;
+ int locked = 1;
+
+ if (oops_in_progress)
+ locked = spin_trylock_irqsave(&sport->port.lock, flags);
+ else
+ spin_lock_irqsave(&sport->port.lock, flags);
+
+ /* first save CR2 and then disable interrupts */
+ cr = old_cr = lpuart32_read(&sport->port, UARTCTRL);
+ cr |= UARTCTRL_TE | UARTCTRL_RE;
+ cr &= ~(UARTCTRL_TIE | UARTCTRL_TCIE | UARTCTRL_RIE);
+ lpuart32_write(&sport->port, cr, UARTCTRL);
+
+ uart_console_write(&sport->port, s, count, lpuart32_console_putchar);
+
+ /* wait for transmitter finish complete and restore CR2 */
+ lpuart32_wait_bit_set(&sport->port, UARTSTAT, UARTSTAT_TC);
+
+ lpuart32_write(&sport->port, old_cr, UARTCTRL);
+
+ if (locked)
+ spin_unlock_irqrestore(&sport->port.lock, flags);
+}
+
+/*
+ * if the port was already initialised (eg, by a boot loader),
+ * try to determine the current setup.
+ */
+static void __init
+lpuart_console_get_options(struct lpuart_port *sport, int *baud,
+ int *parity, int *bits)
+{
+ unsigned char cr, bdh, bdl, brfa;
+ unsigned int sbr, uartclk, baud_raw;
+
+ cr = readb(sport->port.membase + UARTCR2);
+ cr &= UARTCR2_TE | UARTCR2_RE;
+ if (!cr)
+ return;
+
+ /* ok, the port was enabled */
+
+ cr = readb(sport->port.membase + UARTCR1);
+
+ *parity = 'n';
+ if (cr & UARTCR1_PE) {
+ if (cr & UARTCR1_PT)
+ *parity = 'o';
+ else
+ *parity = 'e';
+ }
+
+ if (cr & UARTCR1_M)
+ *bits = 9;
+ else
+ *bits = 8;
+
+ bdh = readb(sport->port.membase + UARTBDH);
+ bdh &= UARTBDH_SBR_MASK;
+ bdl = readb(sport->port.membase + UARTBDL);
+ sbr = bdh;
+ sbr <<= 8;
+ sbr |= bdl;
+ brfa = readb(sport->port.membase + UARTCR4);
+ brfa &= UARTCR4_BRFA_MASK;
+
+ uartclk = lpuart_get_baud_clk_rate(sport);
+ /*
+ * baud = mod_clk/(16*(sbr[13]+(brfa)/32)
+ */
+ baud_raw = uartclk / (16 * (sbr + brfa / 32));
+
+ if (*baud != baud_raw)
+ dev_info(sport->port.dev, "Serial: Console lpuart rounded baud rate"
+ "from %d to %d\n", baud_raw, *baud);
+}
+
+static void __init
+lpuart32_console_get_options(struct lpuart_port *sport, int *baud,
+ int *parity, int *bits)
+{
+ unsigned long cr, bd;
+ unsigned int sbr, uartclk, baud_raw;
+
+ cr = lpuart32_read(&sport->port, UARTCTRL);
+ cr &= UARTCTRL_TE | UARTCTRL_RE;
+ if (!cr)
+ return;
+
+ /* ok, the port was enabled */
+
+ cr = lpuart32_read(&sport->port, UARTCTRL);
+
+ *parity = 'n';
+ if (cr & UARTCTRL_PE) {
+ if (cr & UARTCTRL_PT)
+ *parity = 'o';
+ else
+ *parity = 'e';
+ }
+
+ if (cr & UARTCTRL_M)
+ *bits = 9;
+ else
+ *bits = 8;
+
+ bd = lpuart32_read(&sport->port, UARTBAUD);
+ bd &= UARTBAUD_SBR_MASK;
+ if (!bd)
+ return;
+
+ sbr = bd;
+ uartclk = lpuart_get_baud_clk_rate(sport);
+ /*
+ * baud = mod_clk/(16*(sbr[13]+(brfa)/32)
+ */
+ baud_raw = uartclk / (16 * sbr);
+
+ if (*baud != baud_raw)
+ dev_info(sport->port.dev, "Serial: Console lpuart rounded baud rate"
+ "from %d to %d\n", baud_raw, *baud);
+}
+
+static int __init lpuart_console_setup(struct console *co, char *options)
+{
+ struct lpuart_port *sport;
+ int baud = 115200;
+ int bits = 8;
+ int parity = 'n';
+ int flow = 'n';
+
+ /*
+ * check whether an invalid uart number has been specified, and
+ * if so, search for the first available port that does have
+ * console support.
+ */
+ if (co->index == -1 || co->index >= ARRAY_SIZE(lpuart_ports))
+ co->index = 0;
+
+ sport = lpuart_ports[co->index];
+ if (sport == NULL)
+ return -ENODEV;
+
+ if (options)
+ uart_parse_options(options, &baud, &parity, &bits, &flow);
+ else
+ if (lpuart_is_32(sport))
+ lpuart32_console_get_options(sport, &baud, &parity, &bits);
+ else
+ lpuart_console_get_options(sport, &baud, &parity, &bits);
+
+ if (lpuart_is_32(sport))
+ lpuart32_setup_watermark(sport);
+ else
+ lpuart_setup_watermark(sport);
+
+ return uart_set_options(&sport->port, co, baud, parity, bits, flow);
+}
+
+static struct uart_driver lpuart_reg;
+static struct console lpuart_console = {
+ .name = DEV_NAME,
+ .write = lpuart_console_write,
+ .device = uart_console_device,
+ .setup = lpuart_console_setup,
+ .flags = CON_PRINTBUFFER,
+ .index = -1,
+ .data = &lpuart_reg,
+};
+
+static struct console lpuart32_console = {
+ .name = DEV_NAME,
+ .write = lpuart32_console_write,
+ .device = uart_console_device,
+ .setup = lpuart_console_setup,
+ .flags = CON_PRINTBUFFER,
+ .index = -1,
+ .data = &lpuart_reg,
+};
+
+static void lpuart_early_write(struct console *con, const char *s, unsigned n)
+{
+ struct earlycon_device *dev = con->data;
+
+ uart_console_write(&dev->port, s, n, lpuart_console_putchar);
+}
+
+static void lpuart32_early_write(struct console *con, const char *s, unsigned n)
+{
+ struct earlycon_device *dev = con->data;
+
+ uart_console_write(&dev->port, s, n, lpuart32_console_putchar);
+}
+
+static int __init lpuart_early_console_setup(struct earlycon_device *device,
+ const char *opt)
+{
+ if (!device->port.membase)
+ return -ENODEV;
+
+ device->con->write = lpuart_early_write;
+ return 0;
+}
+
+static int __init lpuart32_early_console_setup(struct earlycon_device *device,
+ const char *opt)
+{
+ if (!device->port.membase)
+ return -ENODEV;
+
+ if (device->port.iotype != UPIO_MEM32)
+ device->port.iotype = UPIO_MEM32BE;
+
+ device->con->write = lpuart32_early_write;
+ return 0;
+}
+
+static int __init ls1028a_early_console_setup(struct earlycon_device *device,
+ const char *opt)
+{
+ u32 cr;
+
+ if (!device->port.membase)
+ return -ENODEV;
+
+ device->port.iotype = UPIO_MEM32;
+ device->con->write = lpuart32_early_write;
+
+ /* set the baudrate */
+ if (device->port.uartclk && device->baud)
+ __lpuart32_serial_setbrg(&device->port, device->baud,
+ false, false);
+
+ /* enable transmitter */
+ cr = lpuart32_read(&device->port, UARTCTRL);
+ cr |= UARTCTRL_TE;
+ lpuart32_write(&device->port, cr, UARTCTRL);
+
+ return 0;
+}
+
+static int __init lpuart32_imx_early_console_setup(struct earlycon_device *device,
+ const char *opt)
+{
+ if (!device->port.membase)
+ return -ENODEV;
+
+ device->port.iotype = UPIO_MEM32;
+ device->port.membase += IMX_REG_OFF;
+ device->con->write = lpuart32_early_write;
+
+ return 0;
+}
+OF_EARLYCON_DECLARE(lpuart, "fsl,vf610-lpuart", lpuart_early_console_setup);
+OF_EARLYCON_DECLARE(lpuart32, "fsl,ls1021a-lpuart", lpuart32_early_console_setup);
+OF_EARLYCON_DECLARE(lpuart32, "fsl,ls1028a-lpuart", ls1028a_early_console_setup);
+OF_EARLYCON_DECLARE(lpuart32, "fsl,imx7ulp-lpuart", lpuart32_imx_early_console_setup);
+OF_EARLYCON_DECLARE(lpuart32, "fsl,imx8ulp-lpuart", lpuart32_imx_early_console_setup);
+OF_EARLYCON_DECLARE(lpuart32, "fsl,imx8qxp-lpuart", lpuart32_imx_early_console_setup);
+OF_EARLYCON_DECLARE(lpuart32, "fsl,imxrt1050-lpuart", lpuart32_imx_early_console_setup);
+EARLYCON_DECLARE(lpuart, lpuart_early_console_setup);
+EARLYCON_DECLARE(lpuart32, lpuart32_early_console_setup);
+
+#define LPUART_CONSOLE (&lpuart_console)
+#define LPUART32_CONSOLE (&lpuart32_console)
+#else
+#define LPUART_CONSOLE NULL
+#define LPUART32_CONSOLE NULL
+#endif
+
+static struct uart_driver lpuart_reg = {
+ .owner = THIS_MODULE,
+ .driver_name = DRIVER_NAME,
+ .dev_name = DEV_NAME,
+ .nr = ARRAY_SIZE(lpuart_ports),
+ .cons = LPUART_CONSOLE,
+};
+
+static const struct serial_rs485 lpuart_rs485_supported = {
+ .flags = SER_RS485_ENABLED | SER_RS485_RTS_ON_SEND | SER_RS485_RTS_AFTER_SEND,
+ /* delay_rts_* and RX_DURING_TX are not supported */
+};
+
+static int lpuart_global_reset(struct lpuart_port *sport)
+{
+ struct uart_port *port = &sport->port;
+ void __iomem *global_addr;
+ unsigned long ctrl, bd;
+ unsigned int val = 0;
+ int ret;
+
+ ret = clk_prepare_enable(sport->ipg_clk);
+ if (ret) {
+ dev_err(sport->port.dev, "failed to enable uart ipg clk: %d\n", ret);
+ return ret;
+ }
+
+ if (is_imx7ulp_lpuart(sport) || is_imx8qxp_lpuart(sport)) {
+ /*
+ * If the transmitter is used by earlycon, wait for transmit engine to
+ * complete and then reset.
+ */
+ ctrl = lpuart32_read(port, UARTCTRL);
+ if (ctrl & UARTCTRL_TE) {
+ bd = lpuart32_read(&sport->port, UARTBAUD);
+ if (read_poll_timeout(lpuart32_tx_empty, val, val, 1, 100000, false,
+ port)) {
+ dev_warn(sport->port.dev,
+ "timeout waiting for transmit engine to complete\n");
+ clk_disable_unprepare(sport->ipg_clk);
+ return 0;
+ }
+ }
+
+ global_addr = port->membase + UART_GLOBAL - IMX_REG_OFF;
+ writel(UART_GLOBAL_RST, global_addr);
+ usleep_range(GLOBAL_RST_MIN_US, GLOBAL_RST_MAX_US);
+ writel(0, global_addr);
+ usleep_range(GLOBAL_RST_MIN_US, GLOBAL_RST_MAX_US);
+
+ /* Recover the transmitter for earlycon. */
+ if (ctrl & UARTCTRL_TE) {
+ lpuart32_write(port, bd, UARTBAUD);
+ lpuart32_write(port, ctrl, UARTCTRL);
+ }
+ }
+
+ clk_disable_unprepare(sport->ipg_clk);
+ return 0;
+}
+
+static int lpuart_probe(struct platform_device *pdev)
+{
+ const struct lpuart_soc_data *sdata = of_device_get_match_data(&pdev->dev);
+ struct device_node *np = pdev->dev.of_node;
+ struct lpuart_port *sport;
+ struct resource *res;
+ irq_handler_t handler;
+ int ret;
+
+ sport = devm_kzalloc(&pdev->dev, sizeof(*sport), GFP_KERNEL);
+ if (!sport)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ sport->port.membase = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(sport->port.membase))
+ return PTR_ERR(sport->port.membase);
+
+ sport->port.membase += sdata->reg_off;
+ sport->port.mapbase = res->start + sdata->reg_off;
+ sport->port.dev = &pdev->dev;
+ sport->port.type = PORT_LPUART;
+ sport->devtype = sdata->devtype;
+ sport->rx_watermark = sdata->rx_watermark;
+ ret = platform_get_irq(pdev, 0);
+ if (ret < 0)
+ return ret;
+ sport->port.irq = ret;
+ sport->port.iotype = sdata->iotype;
+ if (lpuart_is_32(sport))
+ sport->port.ops = &lpuart32_pops;
+ else
+ sport->port.ops = &lpuart_pops;
+ sport->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_FSL_LPUART_CONSOLE);
+ sport->port.flags = UPF_BOOT_AUTOCONF;
+
+ if (lpuart_is_32(sport))
+ sport->port.rs485_config = lpuart32_config_rs485;
+ else
+ sport->port.rs485_config = lpuart_config_rs485;
+ sport->port.rs485_supported = lpuart_rs485_supported;
+
+ sport->ipg_clk = devm_clk_get(&pdev->dev, "ipg");
+ if (IS_ERR(sport->ipg_clk)) {
+ ret = PTR_ERR(sport->ipg_clk);
+ dev_err(&pdev->dev, "failed to get uart ipg clk: %d\n", ret);
+ return ret;
+ }
+
+ sport->baud_clk = NULL;
+ if (is_imx8qxp_lpuart(sport)) {
+ sport->baud_clk = devm_clk_get(&pdev->dev, "baud");
+ if (IS_ERR(sport->baud_clk)) {
+ ret = PTR_ERR(sport->baud_clk);
+ dev_err(&pdev->dev, "failed to get uart baud clk: %d\n", ret);
+ return ret;
+ }
+ }
+
+ ret = of_alias_get_id(np, "serial");
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to get alias id, errno %d\n", ret);
+ return ret;
+ }
+ if (ret >= ARRAY_SIZE(lpuart_ports)) {
+ dev_err(&pdev->dev, "serial%d out of range\n", ret);
+ return -EINVAL;
+ }
+ sport->port.line = ret;
+
+ ret = lpuart_enable_clks(sport);
+ if (ret)
+ return ret;
+ sport->port.uartclk = lpuart_get_baud_clk_rate(sport);
+
+ lpuart_ports[sport->port.line] = sport;
+
+ platform_set_drvdata(pdev, &sport->port);
+
+ if (lpuart_is_32(sport)) {
+ lpuart_reg.cons = LPUART32_CONSOLE;
+ handler = lpuart32_int;
+ } else {
+ lpuart_reg.cons = LPUART_CONSOLE;
+ handler = lpuart_int;
+ }
+
+ ret = lpuart_global_reset(sport);
+ if (ret)
+ goto failed_reset;
+
+ ret = uart_get_rs485_mode(&sport->port);
+ if (ret)
+ goto failed_get_rs485;
+
+ ret = uart_add_one_port(&lpuart_reg, &sport->port);
+ if (ret)
+ goto failed_attach_port;
+
+ ret = devm_request_irq(&pdev->dev, sport->port.irq, handler, 0,
+ DRIVER_NAME, sport);
+ if (ret)
+ goto failed_irq_request;
+
+ return 0;
+
+failed_irq_request:
+ uart_remove_one_port(&lpuart_reg, &sport->port);
+failed_attach_port:
+failed_get_rs485:
+failed_reset:
+ lpuart_disable_clks(sport);
+ return ret;
+}
+
+static int lpuart_remove(struct platform_device *pdev)
+{
+ struct lpuart_port *sport = platform_get_drvdata(pdev);
+
+ uart_remove_one_port(&lpuart_reg, &sport->port);
+
+ lpuart_disable_clks(sport);
+
+ if (sport->dma_tx_chan)
+ dma_release_channel(sport->dma_tx_chan);
+
+ if (sport->dma_rx_chan)
+ dma_release_channel(sport->dma_rx_chan);
+
+ return 0;
+}
+
+static int __maybe_unused lpuart_suspend(struct device *dev)
+{
+ struct lpuart_port *sport = dev_get_drvdata(dev);
+ unsigned long temp;
+ bool irq_wake;
+
+ if (lpuart_is_32(sport)) {
+ /* disable Rx/Tx and interrupts */
+ temp = lpuart32_read(&sport->port, UARTCTRL);
+ temp &= ~(UARTCTRL_TE | UARTCTRL_TIE | UARTCTRL_TCIE);
+ lpuart32_write(&sport->port, temp, UARTCTRL);
+ } else {
+ /* disable Rx/Tx and interrupts */
+ temp = readb(sport->port.membase + UARTCR2);
+ temp &= ~(UARTCR2_TE | UARTCR2_TIE | UARTCR2_TCIE);
+ writeb(temp, sport->port.membase + UARTCR2);
+ }
+
+ uart_suspend_port(&lpuart_reg, &sport->port);
+
+ /* uart_suspend_port() might set wakeup flag */
+ irq_wake = irqd_is_wakeup_set(irq_get_irq_data(sport->port.irq));
+
+ if (sport->lpuart_dma_rx_use) {
+ /*
+ * EDMA driver during suspend will forcefully release any
+ * non-idle DMA channels. If port wakeup is enabled or if port
+ * is console port or 'no_console_suspend' is set the Rx DMA
+ * cannot resume as expected, hence gracefully release the
+ * Rx DMA path before suspend and start Rx DMA path on resume.
+ */
+ if (irq_wake) {
+ lpuart_dma_rx_free(&sport->port);
+ }
+
+ /* Disable Rx DMA to use UART port as wakeup source */
+ if (lpuart_is_32(sport)) {
+ 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);
+ }
+ }
+
+ if (sport->lpuart_dma_tx_use) {
+ sport->dma_tx_in_progress = false;
+ dmaengine_terminate_sync(sport->dma_tx_chan);
+ }
+
+ if (sport->port.suspended && !irq_wake)
+ lpuart_disable_clks(sport);
+
+ return 0;
+}
+
+static int __maybe_unused lpuart_resume(struct device *dev)
+{
+ struct lpuart_port *sport = dev_get_drvdata(dev);
+ bool irq_wake = irqd_is_wakeup_set(irq_get_irq_data(sport->port.irq));
+
+ if (sport->port.suspended && !irq_wake)
+ lpuart_enable_clks(sport);
+
+ if (lpuart_is_32(sport))
+ lpuart32_setup_watermark_enable(sport);
+ else
+ lpuart_setup_watermark_enable(sport);
+
+ if (sport->lpuart_dma_rx_use) {
+ if (irq_wake) {
+ if (!lpuart_start_rx_dma(sport))
+ rx_dma_timer_init(sport);
+ else
+ sport->lpuart_dma_rx_use = false;
+ }
+ }
+
+ lpuart_tx_dma_startup(sport);
+
+ if (lpuart_is_32(sport))
+ lpuart32_configure(sport);
+
+ uart_resume_port(&lpuart_reg, &sport->port);
+
+ return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(lpuart_pm_ops, lpuart_suspend, lpuart_resume);
+
+static struct platform_driver lpuart_driver = {
+ .probe = lpuart_probe,
+ .remove = lpuart_remove,
+ .driver = {
+ .name = "fsl-lpuart",
+ .of_match_table = lpuart_dt_ids,
+ .pm = &lpuart_pm_ops,
+ },
+};
+
+static int __init lpuart_serial_init(void)
+{
+ int ret = uart_register_driver(&lpuart_reg);
+
+ if (ret)
+ return ret;
+
+ ret = platform_driver_register(&lpuart_driver);
+ if (ret)
+ uart_unregister_driver(&lpuart_reg);
+
+ return ret;
+}
+
+static void __exit lpuart_serial_exit(void)
+{
+ platform_driver_unregister(&lpuart_driver);
+ uart_unregister_driver(&lpuart_reg);
+}
+
+module_init(lpuart_serial_init);
+module_exit(lpuart_serial_exit);
+
+MODULE_DESCRIPTION("Freescale lpuart serial port driver");
+MODULE_LICENSE("GPL v2");