1 // SPDX-License-Identifier: GPL-2.0
3 * Driver for msm7k serial device and console
5 * Copyright (C) 2007 Google, Inc.
6 * Author: Robert Love <rlove@google.com>
7 * Copyright (c) 2011, Code Aurora Forum. All rights reserved.
10 #include <linux/kernel.h>
11 #include <linux/atomic.h>
12 #include <linux/dma/qcom_adm.h>
13 #include <linux/dma-mapping.h>
14 #include <linux/dmaengine.h>
15 #include <linux/module.h>
17 #include <linux/ioport.h>
18 #include <linux/interrupt.h>
19 #include <linux/init.h>
20 #include <linux/console.h>
21 #include <linux/tty.h>
22 #include <linux/tty_flip.h>
23 #include <linux/serial_core.h>
24 #include <linux/slab.h>
25 #include <linux/clk.h>
26 #include <linux/platform_device.h>
27 #include <linux/pm_opp.h>
28 #include <linux/delay.h>
30 #include <linux/of_device.h>
31 #include <linux/wait.h>
33 #define MSM_UART_MR1 0x0000
35 #define MSM_UART_MR1_AUTO_RFR_LEVEL0 0x3F
36 #define MSM_UART_MR1_AUTO_RFR_LEVEL1 0x3FF00
37 #define MSM_UART_DM_MR1_AUTO_RFR_LEVEL1 0xFFFFFF00
38 #define MSM_UART_MR1_RX_RDY_CTL BIT(7)
39 #define MSM_UART_MR1_CTS_CTL BIT(6)
41 #define MSM_UART_MR2 0x0004
42 #define MSM_UART_MR2_ERROR_MODE BIT(6)
43 #define MSM_UART_MR2_BITS_PER_CHAR 0x30
44 #define MSM_UART_MR2_BITS_PER_CHAR_5 (0x0 << 4)
45 #define MSM_UART_MR2_BITS_PER_CHAR_6 (0x1 << 4)
46 #define MSM_UART_MR2_BITS_PER_CHAR_7 (0x2 << 4)
47 #define MSM_UART_MR2_BITS_PER_CHAR_8 (0x3 << 4)
48 #define MSM_UART_MR2_STOP_BIT_LEN_ONE (0x1 << 2)
49 #define MSM_UART_MR2_STOP_BIT_LEN_TWO (0x3 << 2)
50 #define MSM_UART_MR2_PARITY_MODE_NONE 0x0
51 #define MSM_UART_MR2_PARITY_MODE_ODD 0x1
52 #define MSM_UART_MR2_PARITY_MODE_EVEN 0x2
53 #define MSM_UART_MR2_PARITY_MODE_SPACE 0x3
54 #define MSM_UART_MR2_PARITY_MODE 0x3
56 #define MSM_UART_CSR 0x0008
58 #define MSM_UART_TF 0x000C
59 #define UARTDM_TF 0x0070
61 #define MSM_UART_CR 0x0010
62 #define MSM_UART_CR_CMD_NULL (0 << 4)
63 #define MSM_UART_CR_CMD_RESET_RX (1 << 4)
64 #define MSM_UART_CR_CMD_RESET_TX (2 << 4)
65 #define MSM_UART_CR_CMD_RESET_ERR (3 << 4)
66 #define MSM_UART_CR_CMD_RESET_BREAK_INT (4 << 4)
67 #define MSM_UART_CR_CMD_START_BREAK (5 << 4)
68 #define MSM_UART_CR_CMD_STOP_BREAK (6 << 4)
69 #define MSM_UART_CR_CMD_RESET_CTS (7 << 4)
70 #define MSM_UART_CR_CMD_RESET_STALE_INT (8 << 4)
71 #define MSM_UART_CR_CMD_PACKET_MODE (9 << 4)
72 #define MSM_UART_CR_CMD_MODE_RESET (12 << 4)
73 #define MSM_UART_CR_CMD_SET_RFR (13 << 4)
74 #define MSM_UART_CR_CMD_RESET_RFR (14 << 4)
75 #define MSM_UART_CR_CMD_PROTECTION_EN (16 << 4)
76 #define MSM_UART_CR_CMD_STALE_EVENT_DISABLE (6 << 8)
77 #define MSM_UART_CR_CMD_STALE_EVENT_ENABLE (80 << 4)
78 #define MSM_UART_CR_CMD_FORCE_STALE (4 << 8)
79 #define MSM_UART_CR_CMD_RESET_TX_READY (3 << 8)
80 #define MSM_UART_CR_TX_DISABLE BIT(3)
81 #define MSM_UART_CR_TX_ENABLE BIT(2)
82 #define MSM_UART_CR_RX_DISABLE BIT(1)
83 #define MSM_UART_CR_RX_ENABLE BIT(0)
84 #define MSM_UART_CR_CMD_RESET_RXBREAK_START ((1 << 11) | (2 << 4))
86 #define MSM_UART_IMR 0x0014
87 #define MSM_UART_IMR_TXLEV BIT(0)
88 #define MSM_UART_IMR_RXSTALE BIT(3)
89 #define MSM_UART_IMR_RXLEV BIT(4)
90 #define MSM_UART_IMR_DELTA_CTS BIT(5)
91 #define MSM_UART_IMR_CURRENT_CTS BIT(6)
92 #define MSM_UART_IMR_RXBREAK_START BIT(10)
94 #define MSM_UART_IPR_RXSTALE_LAST 0x20
95 #define MSM_UART_IPR_STALE_LSB 0x1F
96 #define MSM_UART_IPR_STALE_TIMEOUT_MSB 0x3FF80
97 #define MSM_UART_DM_IPR_STALE_TIMEOUT_MSB 0xFFFFFF80
99 #define MSM_UART_IPR 0x0018
100 #define MSM_UART_TFWR 0x001C
101 #define MSM_UART_RFWR 0x0020
102 #define MSM_UART_HCR 0x0024
104 #define MSM_UART_MREG 0x0028
105 #define MSM_UART_NREG 0x002C
106 #define MSM_UART_DREG 0x0030
107 #define MSM_UART_MNDREG 0x0034
108 #define MSM_UART_IRDA 0x0038
109 #define MSM_UART_MISR_MODE 0x0040
110 #define MSM_UART_MISR_RESET 0x0044
111 #define MSM_UART_MISR_EXPORT 0x0048
112 #define MSM_UART_MISR_VAL 0x004C
113 #define MSM_UART_TEST_CTRL 0x0050
115 #define MSM_UART_SR 0x0008
116 #define MSM_UART_SR_HUNT_CHAR BIT(7)
117 #define MSM_UART_SR_RX_BREAK BIT(6)
118 #define MSM_UART_SR_PAR_FRAME_ERR BIT(5)
119 #define MSM_UART_SR_OVERRUN BIT(4)
120 #define MSM_UART_SR_TX_EMPTY BIT(3)
121 #define MSM_UART_SR_TX_READY BIT(2)
122 #define MSM_UART_SR_RX_FULL BIT(1)
123 #define MSM_UART_SR_RX_READY BIT(0)
125 #define MSM_UART_RF 0x000C
126 #define UARTDM_RF 0x0070
127 #define MSM_UART_MISR 0x0010
128 #define MSM_UART_ISR 0x0014
129 #define MSM_UART_ISR_TX_READY BIT(7)
131 #define UARTDM_RXFS 0x50
132 #define UARTDM_RXFS_BUF_SHIFT 0x7
133 #define UARTDM_RXFS_BUF_MASK 0x7
135 #define UARTDM_DMEN 0x3C
136 #define UARTDM_DMEN_RX_SC_ENABLE BIT(5)
137 #define UARTDM_DMEN_TX_SC_ENABLE BIT(4)
139 #define UARTDM_DMEN_TX_BAM_ENABLE BIT(2) /* UARTDM_1P4 */
140 #define UARTDM_DMEN_TX_DM_ENABLE BIT(0) /* < UARTDM_1P4 */
142 #define UARTDM_DMEN_RX_BAM_ENABLE BIT(3) /* UARTDM_1P4 */
143 #define UARTDM_DMEN_RX_DM_ENABLE BIT(1) /* < UARTDM_1P4 */
145 #define UARTDM_DMRX 0x34
146 #define UARTDM_NCF_TX 0x40
147 #define UARTDM_RX_TOTAL_SNAP 0x38
149 #define UARTDM_BURST_SIZE 16 /* in bytes */
150 #define UARTDM_TX_AIGN(x) ((x) & ~0x3) /* valid for > 1p3 */
151 #define UARTDM_TX_MAX 256 /* in bytes, valid for <= 1p3 */
152 #define UARTDM_RX_SIZE (UART_XMIT_SIZE / 4)
162 struct dma_chan *chan;
163 enum dma_data_direction dir;
169 struct dma_async_tx_descriptor *desc;
173 struct uart_port uart;
179 unsigned int old_snap_state;
181 struct msm_dma tx_dma;
182 struct msm_dma rx_dma;
185 static inline struct msm_port *to_msm_port(struct uart_port *up)
187 return container_of(up, struct msm_port, uart);
191 void msm_write(struct uart_port *port, unsigned int val, unsigned int off)
193 writel_relaxed(val, port->membase + off);
197 unsigned int msm_read(struct uart_port *port, unsigned int off)
199 return readl_relaxed(port->membase + off);
203 * Setup the MND registers to use the TCXO clock.
205 static void msm_serial_set_mnd_regs_tcxo(struct uart_port *port)
207 msm_write(port, 0x06, MSM_UART_MREG);
208 msm_write(port, 0xF1, MSM_UART_NREG);
209 msm_write(port, 0x0F, MSM_UART_DREG);
210 msm_write(port, 0x1A, MSM_UART_MNDREG);
211 port->uartclk = 1843200;
215 * Setup the MND registers to use the TCXO clock divided by 4.
217 static void msm_serial_set_mnd_regs_tcxoby4(struct uart_port *port)
219 msm_write(port, 0x18, MSM_UART_MREG);
220 msm_write(port, 0xF6, MSM_UART_NREG);
221 msm_write(port, 0x0F, MSM_UART_DREG);
222 msm_write(port, 0x0A, MSM_UART_MNDREG);
223 port->uartclk = 1843200;
226 static void msm_serial_set_mnd_regs(struct uart_port *port)
228 struct msm_port *msm_port = to_msm_port(port);
231 * These registers don't exist so we change the clk input rate
232 * on uartdm hardware instead
234 if (msm_port->is_uartdm)
237 if (port->uartclk == 19200000)
238 msm_serial_set_mnd_regs_tcxo(port);
239 else if (port->uartclk == 4800000)
240 msm_serial_set_mnd_regs_tcxoby4(port);
243 static void msm_handle_tx(struct uart_port *port);
244 static void msm_start_rx_dma(struct msm_port *msm_port);
246 static void msm_stop_dma(struct uart_port *port, struct msm_dma *dma)
248 struct device *dev = port->dev;
255 dmaengine_terminate_all(dma->chan);
258 * DMA Stall happens if enqueue and flush command happens concurrently.
259 * For example before changing the baud rate/protocol configuration and
260 * sending flush command to ADM, disable the channel of UARTDM.
261 * Note: should not reset the receiver here immediately as it is not
262 * suggested to do disable/reset or reset/disable at the same time.
264 val = msm_read(port, UARTDM_DMEN);
265 val &= ~dma->enable_bit;
266 msm_write(port, val, UARTDM_DMEN);
269 dma_unmap_single(dev, dma->phys, mapped, dma->dir);
272 static void msm_release_dma(struct msm_port *msm_port)
276 dma = &msm_port->tx_dma;
278 msm_stop_dma(&msm_port->uart, dma);
279 dma_release_channel(dma->chan);
282 memset(dma, 0, sizeof(*dma));
284 dma = &msm_port->rx_dma;
286 msm_stop_dma(&msm_port->uart, dma);
287 dma_release_channel(dma->chan);
291 memset(dma, 0, sizeof(*dma));
294 static void msm_request_tx_dma(struct msm_port *msm_port, resource_size_t base)
296 struct device *dev = msm_port->uart.dev;
297 struct dma_slave_config conf;
298 struct qcom_adm_peripheral_config periph_conf = {};
303 dma = &msm_port->tx_dma;
305 /* allocate DMA resources, if available */
306 dma->chan = dma_request_chan(dev, "tx");
307 if (IS_ERR(dma->chan))
310 of_property_read_u32(dev->of_node, "qcom,tx-crci", &crci);
312 memset(&conf, 0, sizeof(conf));
313 conf.direction = DMA_MEM_TO_DEV;
314 conf.device_fc = true;
315 conf.dst_addr = base + UARTDM_TF;
316 conf.dst_maxburst = UARTDM_BURST_SIZE;
318 conf.peripheral_config = &periph_conf;
319 conf.peripheral_size = sizeof(periph_conf);
320 periph_conf.crci = crci;
323 ret = dmaengine_slave_config(dma->chan, &conf);
327 dma->dir = DMA_TO_DEVICE;
329 if (msm_port->is_uartdm < UARTDM_1P4)
330 dma->enable_bit = UARTDM_DMEN_TX_DM_ENABLE;
332 dma->enable_bit = UARTDM_DMEN_TX_BAM_ENABLE;
337 dma_release_channel(dma->chan);
339 memset(dma, 0, sizeof(*dma));
342 static void msm_request_rx_dma(struct msm_port *msm_port, resource_size_t base)
344 struct device *dev = msm_port->uart.dev;
345 struct dma_slave_config conf;
346 struct qcom_adm_peripheral_config periph_conf = {};
351 dma = &msm_port->rx_dma;
353 /* allocate DMA resources, if available */
354 dma->chan = dma_request_chan(dev, "rx");
355 if (IS_ERR(dma->chan))
358 of_property_read_u32(dev->of_node, "qcom,rx-crci", &crci);
360 dma->virt = kzalloc(UARTDM_RX_SIZE, GFP_KERNEL);
364 memset(&conf, 0, sizeof(conf));
365 conf.direction = DMA_DEV_TO_MEM;
366 conf.device_fc = true;
367 conf.src_addr = base + UARTDM_RF;
368 conf.src_maxburst = UARTDM_BURST_SIZE;
370 conf.peripheral_config = &periph_conf;
371 conf.peripheral_size = sizeof(periph_conf);
372 periph_conf.crci = crci;
375 ret = dmaengine_slave_config(dma->chan, &conf);
379 dma->dir = DMA_FROM_DEVICE;
381 if (msm_port->is_uartdm < UARTDM_1P4)
382 dma->enable_bit = UARTDM_DMEN_RX_DM_ENABLE;
384 dma->enable_bit = UARTDM_DMEN_RX_BAM_ENABLE;
390 dma_release_channel(dma->chan);
392 memset(dma, 0, sizeof(*dma));
395 static inline void msm_wait_for_xmitr(struct uart_port *port)
397 unsigned int timeout = 500000;
399 while (!(msm_read(port, MSM_UART_SR) & MSM_UART_SR_TX_EMPTY)) {
400 if (msm_read(port, MSM_UART_ISR) & MSM_UART_ISR_TX_READY)
406 msm_write(port, MSM_UART_CR_CMD_RESET_TX_READY, MSM_UART_CR);
409 static void msm_stop_tx(struct uart_port *port)
411 struct msm_port *msm_port = to_msm_port(port);
413 msm_port->imr &= ~MSM_UART_IMR_TXLEV;
414 msm_write(port, msm_port->imr, MSM_UART_IMR);
417 static void msm_start_tx(struct uart_port *port)
419 struct msm_port *msm_port = to_msm_port(port);
420 struct msm_dma *dma = &msm_port->tx_dma;
422 /* Already started in DMA mode */
426 msm_port->imr |= MSM_UART_IMR_TXLEV;
427 msm_write(port, msm_port->imr, MSM_UART_IMR);
430 static void msm_reset_dm_count(struct uart_port *port, int count)
432 msm_wait_for_xmitr(port);
433 msm_write(port, count, UARTDM_NCF_TX);
434 msm_read(port, UARTDM_NCF_TX);
437 static void msm_complete_tx_dma(void *args)
439 struct msm_port *msm_port = args;
440 struct uart_port *port = &msm_port->uart;
441 struct circ_buf *xmit = &port->state->xmit;
442 struct msm_dma *dma = &msm_port->tx_dma;
443 struct dma_tx_state state;
448 uart_port_lock_irqsave(port, &flags);
450 /* Already stopped */
454 dmaengine_tx_status(dma->chan, dma->cookie, &state);
456 dma_unmap_single(port->dev, dma->phys, dma->count, dma->dir);
458 val = msm_read(port, UARTDM_DMEN);
459 val &= ~dma->enable_bit;
460 msm_write(port, val, UARTDM_DMEN);
462 if (msm_port->is_uartdm > UARTDM_1P3) {
463 msm_write(port, MSM_UART_CR_CMD_RESET_TX, MSM_UART_CR);
464 msm_write(port, MSM_UART_CR_TX_ENABLE, MSM_UART_CR);
467 count = dma->count - state.residue;
468 uart_xmit_advance(port, count);
471 /* Restore "Tx FIFO below watermark" interrupt */
472 msm_port->imr |= MSM_UART_IMR_TXLEV;
473 msm_write(port, msm_port->imr, MSM_UART_IMR);
475 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
476 uart_write_wakeup(port);
480 uart_port_unlock_irqrestore(port, flags);
483 static int msm_handle_tx_dma(struct msm_port *msm_port, unsigned int count)
485 struct circ_buf *xmit = &msm_port->uart.state->xmit;
486 struct uart_port *port = &msm_port->uart;
487 struct msm_dma *dma = &msm_port->tx_dma;
492 cpu_addr = &xmit->buf[xmit->tail];
494 dma->phys = dma_map_single(port->dev, cpu_addr, count, dma->dir);
495 ret = dma_mapping_error(port->dev, dma->phys);
499 dma->desc = dmaengine_prep_slave_single(dma->chan, dma->phys,
500 count, DMA_MEM_TO_DEV,
508 dma->desc->callback = msm_complete_tx_dma;
509 dma->desc->callback_param = msm_port;
511 dma->cookie = dmaengine_submit(dma->desc);
512 ret = dma_submit_error(dma->cookie);
517 * Using DMA complete for Tx FIFO reload, no need for
518 * "Tx FIFO below watermark" one, disable it
520 msm_port->imr &= ~MSM_UART_IMR_TXLEV;
521 msm_write(port, msm_port->imr, MSM_UART_IMR);
525 val = msm_read(port, UARTDM_DMEN);
526 val |= dma->enable_bit;
528 if (msm_port->is_uartdm < UARTDM_1P4)
529 msm_write(port, val, UARTDM_DMEN);
531 msm_reset_dm_count(port, count);
533 if (msm_port->is_uartdm > UARTDM_1P3)
534 msm_write(port, val, UARTDM_DMEN);
536 dma_async_issue_pending(dma->chan);
539 dma_unmap_single(port->dev, dma->phys, count, dma->dir);
543 static void msm_complete_rx_dma(void *args)
545 struct msm_port *msm_port = args;
546 struct uart_port *port = &msm_port->uart;
547 struct tty_port *tport = &port->state->port;
548 struct msm_dma *dma = &msm_port->rx_dma;
549 int count = 0, i, sysrq;
553 uart_port_lock_irqsave(port, &flags);
555 /* Already stopped */
559 val = msm_read(port, UARTDM_DMEN);
560 val &= ~dma->enable_bit;
561 msm_write(port, val, UARTDM_DMEN);
563 if (msm_read(port, MSM_UART_SR) & MSM_UART_SR_OVERRUN) {
564 port->icount.overrun++;
565 tty_insert_flip_char(tport, 0, TTY_OVERRUN);
566 msm_write(port, MSM_UART_CR_CMD_RESET_ERR, MSM_UART_CR);
569 count = msm_read(port, UARTDM_RX_TOTAL_SNAP);
571 port->icount.rx += count;
575 dma_unmap_single(port->dev, dma->phys, UARTDM_RX_SIZE, dma->dir);
577 for (i = 0; i < count; i++) {
578 char flag = TTY_NORMAL;
580 if (msm_port->break_detected && dma->virt[i] == 0) {
583 msm_port->break_detected = false;
584 if (uart_handle_break(port))
588 if (!(port->read_status_mask & MSM_UART_SR_RX_BREAK))
591 sysrq = uart_prepare_sysrq_char(port, dma->virt[i]);
593 tty_insert_flip_char(tport, dma->virt[i], flag);
596 msm_start_rx_dma(msm_port);
598 uart_unlock_and_check_sysrq_irqrestore(port, flags);
601 tty_flip_buffer_push(tport);
604 static void msm_start_rx_dma(struct msm_port *msm_port)
606 struct msm_dma *dma = &msm_port->rx_dma;
607 struct uart_port *uart = &msm_port->uart;
611 if (IS_ENABLED(CONFIG_CONSOLE_POLL))
617 dma->phys = dma_map_single(uart->dev, dma->virt,
618 UARTDM_RX_SIZE, dma->dir);
619 ret = dma_mapping_error(uart->dev, dma->phys);
623 dma->desc = dmaengine_prep_slave_single(dma->chan, dma->phys,
624 UARTDM_RX_SIZE, DMA_DEV_TO_MEM,
629 dma->desc->callback = msm_complete_rx_dma;
630 dma->desc->callback_param = msm_port;
632 dma->cookie = dmaengine_submit(dma->desc);
633 ret = dma_submit_error(dma->cookie);
637 * Using DMA for FIFO off-load, no need for "Rx FIFO over
638 * watermark" or "stale" interrupts, disable them
640 msm_port->imr &= ~(MSM_UART_IMR_RXLEV | MSM_UART_IMR_RXSTALE);
643 * Well, when DMA is ADM3 engine(implied by <= UARTDM v1.3),
644 * we need RXSTALE to flush input DMA fifo to memory
646 if (msm_port->is_uartdm < UARTDM_1P4)
647 msm_port->imr |= MSM_UART_IMR_RXSTALE;
649 msm_write(uart, msm_port->imr, MSM_UART_IMR);
651 dma->count = UARTDM_RX_SIZE;
653 dma_async_issue_pending(dma->chan);
655 msm_write(uart, MSM_UART_CR_CMD_RESET_STALE_INT, MSM_UART_CR);
656 msm_write(uart, MSM_UART_CR_CMD_STALE_EVENT_ENABLE, MSM_UART_CR);
658 val = msm_read(uart, UARTDM_DMEN);
659 val |= dma->enable_bit;
661 if (msm_port->is_uartdm < UARTDM_1P4)
662 msm_write(uart, val, UARTDM_DMEN);
664 msm_write(uart, UARTDM_RX_SIZE, UARTDM_DMRX);
666 if (msm_port->is_uartdm > UARTDM_1P3)
667 msm_write(uart, val, UARTDM_DMEN);
671 dma_unmap_single(uart->dev, dma->phys, UARTDM_RX_SIZE, dma->dir);
675 * Switch from DMA to SW/FIFO mode. After clearing Rx BAM (UARTDM_DMEN),
676 * receiver must be reset.
678 msm_write(uart, MSM_UART_CR_CMD_RESET_RX, MSM_UART_CR);
679 msm_write(uart, MSM_UART_CR_RX_ENABLE, MSM_UART_CR);
681 msm_write(uart, MSM_UART_CR_CMD_RESET_STALE_INT, MSM_UART_CR);
682 msm_write(uart, 0xFFFFFF, UARTDM_DMRX);
683 msm_write(uart, MSM_UART_CR_CMD_STALE_EVENT_ENABLE, MSM_UART_CR);
685 /* Re-enable RX interrupts */
686 msm_port->imr |= MSM_UART_IMR_RXLEV | MSM_UART_IMR_RXSTALE;
687 msm_write(uart, msm_port->imr, MSM_UART_IMR);
690 static void msm_stop_rx(struct uart_port *port)
692 struct msm_port *msm_port = to_msm_port(port);
693 struct msm_dma *dma = &msm_port->rx_dma;
695 msm_port->imr &= ~(MSM_UART_IMR_RXLEV | MSM_UART_IMR_RXSTALE);
696 msm_write(port, msm_port->imr, MSM_UART_IMR);
699 msm_stop_dma(port, dma);
702 static void msm_enable_ms(struct uart_port *port)
704 struct msm_port *msm_port = to_msm_port(port);
706 msm_port->imr |= MSM_UART_IMR_DELTA_CTS;
707 msm_write(port, msm_port->imr, MSM_UART_IMR);
710 static void msm_handle_rx_dm(struct uart_port *port, unsigned int misr)
711 __must_hold(&port->lock)
713 struct tty_port *tport = &port->state->port;
716 struct msm_port *msm_port = to_msm_port(port);
718 if ((msm_read(port, MSM_UART_SR) & MSM_UART_SR_OVERRUN)) {
719 port->icount.overrun++;
720 tty_insert_flip_char(tport, 0, TTY_OVERRUN);
721 msm_write(port, MSM_UART_CR_CMD_RESET_ERR, MSM_UART_CR);
724 if (misr & MSM_UART_IMR_RXSTALE) {
725 count = msm_read(port, UARTDM_RX_TOTAL_SNAP) -
726 msm_port->old_snap_state;
727 msm_port->old_snap_state = 0;
729 count = 4 * (msm_read(port, MSM_UART_RFWR));
730 msm_port->old_snap_state += count;
733 /* TODO: Precise error reporting */
735 port->icount.rx += count;
738 unsigned char buf[4];
739 int sysrq, r_count, i;
741 sr = msm_read(port, MSM_UART_SR);
742 if ((sr & MSM_UART_SR_RX_READY) == 0) {
743 msm_port->old_snap_state -= count;
747 ioread32_rep(port->membase + UARTDM_RF, buf, 1);
748 r_count = min_t(int, count, sizeof(buf));
750 for (i = 0; i < r_count; i++) {
751 char flag = TTY_NORMAL;
753 if (msm_port->break_detected && buf[i] == 0) {
756 msm_port->break_detected = false;
757 if (uart_handle_break(port))
761 if (!(port->read_status_mask & MSM_UART_SR_RX_BREAK))
764 sysrq = uart_prepare_sysrq_char(port, buf[i]);
766 tty_insert_flip_char(tport, buf[i], flag);
771 tty_flip_buffer_push(tport);
773 if (misr & (MSM_UART_IMR_RXSTALE))
774 msm_write(port, MSM_UART_CR_CMD_RESET_STALE_INT, MSM_UART_CR);
775 msm_write(port, 0xFFFFFF, UARTDM_DMRX);
776 msm_write(port, MSM_UART_CR_CMD_STALE_EVENT_ENABLE, MSM_UART_CR);
779 msm_start_rx_dma(msm_port);
782 static void msm_handle_rx(struct uart_port *port)
783 __must_hold(&port->lock)
785 struct tty_port *tport = &port->state->port;
789 * Handle overrun. My understanding of the hardware is that overrun
790 * is not tied to the RX buffer, so we handle the case out of band.
792 if ((msm_read(port, MSM_UART_SR) & MSM_UART_SR_OVERRUN)) {
793 port->icount.overrun++;
794 tty_insert_flip_char(tport, 0, TTY_OVERRUN);
795 msm_write(port, MSM_UART_CR_CMD_RESET_ERR, MSM_UART_CR);
798 /* and now the main RX loop */
799 while ((sr = msm_read(port, MSM_UART_SR)) & MSM_UART_SR_RX_READY) {
801 char flag = TTY_NORMAL;
804 c = msm_read(port, MSM_UART_RF);
806 if (sr & MSM_UART_SR_RX_BREAK) {
808 if (uart_handle_break(port))
810 } else if (sr & MSM_UART_SR_PAR_FRAME_ERR) {
811 port->icount.frame++;
816 /* Mask conditions we're ignoring. */
817 sr &= port->read_status_mask;
819 if (sr & MSM_UART_SR_RX_BREAK)
821 else if (sr & MSM_UART_SR_PAR_FRAME_ERR)
824 sysrq = uart_prepare_sysrq_char(port, c);
826 tty_insert_flip_char(tport, c, flag);
829 tty_flip_buffer_push(tport);
832 static void msm_handle_tx_pio(struct uart_port *port, unsigned int tx_count)
834 struct circ_buf *xmit = &port->state->xmit;
835 struct msm_port *msm_port = to_msm_port(port);
836 unsigned int num_chars;
837 unsigned int tf_pointer = 0;
840 if (msm_port->is_uartdm)
841 tf = port->membase + UARTDM_TF;
843 tf = port->membase + MSM_UART_TF;
845 if (tx_count && msm_port->is_uartdm)
846 msm_reset_dm_count(port, tx_count);
848 while (tf_pointer < tx_count) {
852 if (!(msm_read(port, MSM_UART_SR) & MSM_UART_SR_TX_READY))
855 if (msm_port->is_uartdm)
856 num_chars = min(tx_count - tf_pointer,
857 (unsigned int)sizeof(buf));
861 for (i = 0; i < num_chars; i++)
862 buf[i] = xmit->buf[xmit->tail + i];
864 iowrite32_rep(tf, buf, 1);
865 uart_xmit_advance(port, num_chars);
866 tf_pointer += num_chars;
869 /* disable tx interrupts if nothing more to send */
870 if (uart_circ_empty(xmit))
873 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
874 uart_write_wakeup(port);
877 static void msm_handle_tx(struct uart_port *port)
879 struct msm_port *msm_port = to_msm_port(port);
880 struct circ_buf *xmit = &msm_port->uart.state->xmit;
881 struct msm_dma *dma = &msm_port->tx_dma;
882 unsigned int pio_count, dma_count, dma_min;
888 if (msm_port->is_uartdm)
889 tf = port->membase + UARTDM_TF;
891 tf = port->membase + MSM_UART_TF;
893 buf[0] = port->x_char;
895 if (msm_port->is_uartdm)
896 msm_reset_dm_count(port, 1);
898 iowrite32_rep(tf, buf, 1);
904 if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
909 pio_count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
910 dma_count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
912 dma_min = 1; /* Always DMA */
913 if (msm_port->is_uartdm > UARTDM_1P3) {
914 dma_count = UARTDM_TX_AIGN(dma_count);
915 dma_min = UARTDM_BURST_SIZE;
917 if (dma_count > UARTDM_TX_MAX)
918 dma_count = UARTDM_TX_MAX;
921 if (pio_count > port->fifosize)
922 pio_count = port->fifosize;
924 if (!dma->chan || dma_count < dma_min)
925 msm_handle_tx_pio(port, pio_count);
927 err = msm_handle_tx_dma(msm_port, dma_count);
929 if (err) /* fall back to PIO mode */
930 msm_handle_tx_pio(port, pio_count);
933 static void msm_handle_delta_cts(struct uart_port *port)
935 msm_write(port, MSM_UART_CR_CMD_RESET_CTS, MSM_UART_CR);
937 wake_up_interruptible(&port->state->port.delta_msr_wait);
940 static irqreturn_t msm_uart_irq(int irq, void *dev_id)
942 struct uart_port *port = dev_id;
943 struct msm_port *msm_port = to_msm_port(port);
944 struct msm_dma *dma = &msm_port->rx_dma;
948 uart_port_lock(port);
949 misr = msm_read(port, MSM_UART_MISR);
950 msm_write(port, 0, MSM_UART_IMR); /* disable interrupt */
952 if (misr & MSM_UART_IMR_RXBREAK_START) {
953 msm_port->break_detected = true;
954 msm_write(port, MSM_UART_CR_CMD_RESET_RXBREAK_START, MSM_UART_CR);
957 if (misr & (MSM_UART_IMR_RXLEV | MSM_UART_IMR_RXSTALE)) {
959 val = MSM_UART_CR_CMD_STALE_EVENT_DISABLE;
960 msm_write(port, val, MSM_UART_CR);
961 val = MSM_UART_CR_CMD_RESET_STALE_INT;
962 msm_write(port, val, MSM_UART_CR);
964 * Flush DMA input fifo to memory, this will also
965 * trigger DMA RX completion
967 dmaengine_terminate_all(dma->chan);
968 } else if (msm_port->is_uartdm) {
969 msm_handle_rx_dm(port, misr);
974 if (misr & MSM_UART_IMR_TXLEV)
976 if (misr & MSM_UART_IMR_DELTA_CTS)
977 msm_handle_delta_cts(port);
979 msm_write(port, msm_port->imr, MSM_UART_IMR); /* restore interrupt */
980 uart_unlock_and_check_sysrq(port);
985 static unsigned int msm_tx_empty(struct uart_port *port)
987 return (msm_read(port, MSM_UART_SR) & MSM_UART_SR_TX_EMPTY) ? TIOCSER_TEMT : 0;
990 static unsigned int msm_get_mctrl(struct uart_port *port)
992 return TIOCM_CAR | TIOCM_CTS | TIOCM_DSR | TIOCM_RTS;
995 static void msm_reset(struct uart_port *port)
997 struct msm_port *msm_port = to_msm_port(port);
1000 /* reset everything */
1001 msm_write(port, MSM_UART_CR_CMD_RESET_RX, MSM_UART_CR);
1002 msm_write(port, MSM_UART_CR_CMD_RESET_TX, MSM_UART_CR);
1003 msm_write(port, MSM_UART_CR_CMD_RESET_ERR, MSM_UART_CR);
1004 msm_write(port, MSM_UART_CR_CMD_RESET_BREAK_INT, MSM_UART_CR);
1005 msm_write(port, MSM_UART_CR_CMD_RESET_CTS, MSM_UART_CR);
1006 msm_write(port, MSM_UART_CR_CMD_RESET_RFR, MSM_UART_CR);
1007 mr = msm_read(port, MSM_UART_MR1);
1008 mr &= ~MSM_UART_MR1_RX_RDY_CTL;
1009 msm_write(port, mr, MSM_UART_MR1);
1011 /* Disable DM modes */
1012 if (msm_port->is_uartdm)
1013 msm_write(port, 0, UARTDM_DMEN);
1016 static void msm_set_mctrl(struct uart_port *port, unsigned int mctrl)
1020 mr = msm_read(port, MSM_UART_MR1);
1022 if (!(mctrl & TIOCM_RTS)) {
1023 mr &= ~MSM_UART_MR1_RX_RDY_CTL;
1024 msm_write(port, mr, MSM_UART_MR1);
1025 msm_write(port, MSM_UART_CR_CMD_RESET_RFR, MSM_UART_CR);
1027 mr |= MSM_UART_MR1_RX_RDY_CTL;
1028 msm_write(port, mr, MSM_UART_MR1);
1032 static void msm_break_ctl(struct uart_port *port, int break_ctl)
1035 msm_write(port, MSM_UART_CR_CMD_START_BREAK, MSM_UART_CR);
1037 msm_write(port, MSM_UART_CR_CMD_STOP_BREAK, MSM_UART_CR);
1040 struct msm_baud_map {
1046 static const struct msm_baud_map *
1047 msm_find_best_baud(struct uart_port *port, unsigned int baud,
1048 unsigned long *rate)
1050 struct msm_port *msm_port = to_msm_port(port);
1051 unsigned int divisor, result;
1052 unsigned long target, old, best_rate = 0, diff, best_diff = ULONG_MAX;
1053 const struct msm_baud_map *entry, *end, *best;
1054 static const struct msm_baud_map table[] = {
1073 best = table; /* Default to smallest divider */
1074 target = clk_round_rate(msm_port->clk, 16 * baud);
1075 divisor = DIV_ROUND_CLOSEST(target, 16 * baud);
1077 end = table + ARRAY_SIZE(table);
1079 while (entry < end) {
1080 if (entry->divisor <= divisor) {
1081 result = target / entry->divisor / 16;
1082 diff = abs(result - baud);
1084 /* Keep track of best entry */
1085 if (diff < best_diff) {
1093 } else if (entry->divisor > divisor) {
1095 target = clk_round_rate(msm_port->clk, old + 1);
1097 * The rate didn't get any faster so we can't do
1098 * better at dividing it down
1103 /* Start the divisor search over at this new rate */
1105 divisor = DIV_ROUND_CLOSEST(target, 16 * baud);
1115 static int msm_set_baud_rate(struct uart_port *port, unsigned int baud,
1116 unsigned long *saved_flags)
1117 __must_hold(&port->lock)
1119 unsigned int rxstale, watermark, mask;
1120 struct msm_port *msm_port = to_msm_port(port);
1121 const struct msm_baud_map *entry;
1122 unsigned long flags, rate;
1124 flags = *saved_flags;
1125 uart_port_unlock_irqrestore(port, flags);
1127 entry = msm_find_best_baud(port, baud, &rate);
1128 dev_pm_opp_set_rate(port->dev, rate);
1129 baud = rate / 16 / entry->divisor;
1131 uart_port_lock_irqsave(port, &flags);
1132 *saved_flags = flags;
1133 port->uartclk = rate;
1135 msm_write(port, entry->code, MSM_UART_CSR);
1137 /* RX stale watermark */
1138 rxstale = entry->rxstale;
1139 watermark = MSM_UART_IPR_STALE_LSB & rxstale;
1140 if (msm_port->is_uartdm) {
1141 mask = MSM_UART_DM_IPR_STALE_TIMEOUT_MSB;
1143 watermark |= MSM_UART_IPR_RXSTALE_LAST;
1144 mask = MSM_UART_IPR_STALE_TIMEOUT_MSB;
1147 watermark |= mask & (rxstale << 2);
1149 msm_write(port, watermark, MSM_UART_IPR);
1151 /* set RX watermark */
1152 watermark = (port->fifosize * 3) / 4;
1153 msm_write(port, watermark, MSM_UART_RFWR);
1155 /* set TX watermark */
1156 msm_write(port, 10, MSM_UART_TFWR);
1158 msm_write(port, MSM_UART_CR_CMD_PROTECTION_EN, MSM_UART_CR);
1161 /* Enable RX and TX */
1162 msm_write(port, MSM_UART_CR_TX_ENABLE | MSM_UART_CR_RX_ENABLE, MSM_UART_CR);
1164 /* turn on RX and CTS interrupts */
1165 msm_port->imr = MSM_UART_IMR_RXLEV | MSM_UART_IMR_RXSTALE |
1166 MSM_UART_IMR_CURRENT_CTS | MSM_UART_IMR_RXBREAK_START;
1168 msm_write(port, msm_port->imr, MSM_UART_IMR);
1170 if (msm_port->is_uartdm) {
1171 msm_write(port, MSM_UART_CR_CMD_RESET_STALE_INT, MSM_UART_CR);
1172 msm_write(port, 0xFFFFFF, UARTDM_DMRX);
1173 msm_write(port, MSM_UART_CR_CMD_STALE_EVENT_ENABLE, MSM_UART_CR);
1179 static void msm_init_clock(struct uart_port *port)
1181 struct msm_port *msm_port = to_msm_port(port);
1183 dev_pm_opp_set_rate(port->dev, port->uartclk);
1184 clk_prepare_enable(msm_port->clk);
1185 clk_prepare_enable(msm_port->pclk);
1186 msm_serial_set_mnd_regs(port);
1189 static int msm_startup(struct uart_port *port)
1191 struct msm_port *msm_port = to_msm_port(port);
1192 unsigned int data, rfr_level, mask;
1195 snprintf(msm_port->name, sizeof(msm_port->name),
1196 "msm_serial%d", port->line);
1198 msm_init_clock(port);
1200 if (likely(port->fifosize > 12))
1201 rfr_level = port->fifosize - 12;
1203 rfr_level = port->fifosize;
1205 /* set automatic RFR level */
1206 data = msm_read(port, MSM_UART_MR1);
1208 if (msm_port->is_uartdm)
1209 mask = MSM_UART_DM_MR1_AUTO_RFR_LEVEL1;
1211 mask = MSM_UART_MR1_AUTO_RFR_LEVEL1;
1214 data &= ~MSM_UART_MR1_AUTO_RFR_LEVEL0;
1215 data |= mask & (rfr_level << 2);
1216 data |= MSM_UART_MR1_AUTO_RFR_LEVEL0 & rfr_level;
1217 msm_write(port, data, MSM_UART_MR1);
1219 if (msm_port->is_uartdm) {
1220 msm_request_tx_dma(msm_port, msm_port->uart.mapbase);
1221 msm_request_rx_dma(msm_port, msm_port->uart.mapbase);
1224 ret = request_irq(port->irq, msm_uart_irq, IRQF_TRIGGER_HIGH,
1225 msm_port->name, port);
1232 if (msm_port->is_uartdm)
1233 msm_release_dma(msm_port);
1235 clk_disable_unprepare(msm_port->pclk);
1236 clk_disable_unprepare(msm_port->clk);
1237 dev_pm_opp_set_rate(port->dev, 0);
1242 static void msm_shutdown(struct uart_port *port)
1244 struct msm_port *msm_port = to_msm_port(port);
1247 msm_write(port, 0, MSM_UART_IMR); /* disable interrupts */
1249 if (msm_port->is_uartdm)
1250 msm_release_dma(msm_port);
1252 clk_disable_unprepare(msm_port->clk);
1253 dev_pm_opp_set_rate(port->dev, 0);
1255 free_irq(port->irq, port);
1258 static void msm_set_termios(struct uart_port *port, struct ktermios *termios,
1259 const struct ktermios *old)
1261 struct msm_port *msm_port = to_msm_port(port);
1262 struct msm_dma *dma = &msm_port->rx_dma;
1263 unsigned long flags;
1264 unsigned int baud, mr;
1266 uart_port_lock_irqsave(port, &flags);
1268 if (dma->chan) /* Terminate if any */
1269 msm_stop_dma(port, dma);
1271 /* calculate and set baud rate */
1272 baud = uart_get_baud_rate(port, termios, old, 300, 4000000);
1273 baud = msm_set_baud_rate(port, baud, &flags);
1274 if (tty_termios_baud_rate(termios))
1275 tty_termios_encode_baud_rate(termios, baud, baud);
1277 /* calculate parity */
1278 mr = msm_read(port, MSM_UART_MR2);
1279 mr &= ~MSM_UART_MR2_PARITY_MODE;
1280 if (termios->c_cflag & PARENB) {
1281 if (termios->c_cflag & PARODD)
1282 mr |= MSM_UART_MR2_PARITY_MODE_ODD;
1283 else if (termios->c_cflag & CMSPAR)
1284 mr |= MSM_UART_MR2_PARITY_MODE_SPACE;
1286 mr |= MSM_UART_MR2_PARITY_MODE_EVEN;
1289 /* calculate bits per char */
1290 mr &= ~MSM_UART_MR2_BITS_PER_CHAR;
1291 switch (termios->c_cflag & CSIZE) {
1293 mr |= MSM_UART_MR2_BITS_PER_CHAR_5;
1296 mr |= MSM_UART_MR2_BITS_PER_CHAR_6;
1299 mr |= MSM_UART_MR2_BITS_PER_CHAR_7;
1303 mr |= MSM_UART_MR2_BITS_PER_CHAR_8;
1307 /* calculate stop bits */
1308 mr &= ~(MSM_UART_MR2_STOP_BIT_LEN_ONE | MSM_UART_MR2_STOP_BIT_LEN_TWO);
1309 if (termios->c_cflag & CSTOPB)
1310 mr |= MSM_UART_MR2_STOP_BIT_LEN_TWO;
1312 mr |= MSM_UART_MR2_STOP_BIT_LEN_ONE;
1314 /* set parity, bits per char, and stop bit */
1315 msm_write(port, mr, MSM_UART_MR2);
1317 /* calculate and set hardware flow control */
1318 mr = msm_read(port, MSM_UART_MR1);
1319 mr &= ~(MSM_UART_MR1_CTS_CTL | MSM_UART_MR1_RX_RDY_CTL);
1320 if (termios->c_cflag & CRTSCTS) {
1321 mr |= MSM_UART_MR1_CTS_CTL;
1322 mr |= MSM_UART_MR1_RX_RDY_CTL;
1324 msm_write(port, mr, MSM_UART_MR1);
1326 /* Configure status bits to ignore based on termio flags. */
1327 port->read_status_mask = 0;
1328 if (termios->c_iflag & INPCK)
1329 port->read_status_mask |= MSM_UART_SR_PAR_FRAME_ERR;
1330 if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
1331 port->read_status_mask |= MSM_UART_SR_RX_BREAK;
1333 uart_update_timeout(port, termios->c_cflag, baud);
1335 /* Try to use DMA */
1336 msm_start_rx_dma(msm_port);
1338 uart_port_unlock_irqrestore(port, flags);
1341 static const char *msm_type(struct uart_port *port)
1346 static void msm_release_port(struct uart_port *port)
1348 struct platform_device *pdev = to_platform_device(port->dev);
1349 struct resource *uart_resource;
1350 resource_size_t size;
1352 uart_resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1353 if (unlikely(!uart_resource))
1355 size = resource_size(uart_resource);
1357 release_mem_region(port->mapbase, size);
1358 iounmap(port->membase);
1359 port->membase = NULL;
1362 static int msm_request_port(struct uart_port *port)
1364 struct platform_device *pdev = to_platform_device(port->dev);
1365 struct resource *uart_resource;
1366 resource_size_t size;
1369 uart_resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1370 if (unlikely(!uart_resource))
1373 size = resource_size(uart_resource);
1375 if (!request_mem_region(port->mapbase, size, "msm_serial"))
1378 port->membase = ioremap(port->mapbase, size);
1379 if (!port->membase) {
1381 goto fail_release_port;
1387 release_mem_region(port->mapbase, size);
1391 static void msm_config_port(struct uart_port *port, int flags)
1395 if (flags & UART_CONFIG_TYPE) {
1396 port->type = PORT_MSM;
1397 ret = msm_request_port(port);
1403 static int msm_verify_port(struct uart_port *port, struct serial_struct *ser)
1405 if (unlikely(ser->type != PORT_UNKNOWN && ser->type != PORT_MSM))
1407 if (unlikely(port->irq != ser->irq))
1412 static void msm_power(struct uart_port *port, unsigned int state,
1413 unsigned int oldstate)
1415 struct msm_port *msm_port = to_msm_port(port);
1419 dev_pm_opp_set_rate(port->dev, port->uartclk);
1420 clk_prepare_enable(msm_port->clk);
1421 clk_prepare_enable(msm_port->pclk);
1424 clk_disable_unprepare(msm_port->clk);
1425 dev_pm_opp_set_rate(port->dev, 0);
1426 clk_disable_unprepare(msm_port->pclk);
1429 pr_err("msm_serial: Unknown PM state %d\n", state);
1433 #ifdef CONFIG_CONSOLE_POLL
1434 static int msm_poll_get_char_single(struct uart_port *port)
1436 struct msm_port *msm_port = to_msm_port(port);
1437 unsigned int rf_reg = msm_port->is_uartdm ? UARTDM_RF : MSM_UART_RF;
1439 if (!(msm_read(port, MSM_UART_SR) & MSM_UART_SR_RX_READY))
1440 return NO_POLL_CHAR;
1442 return msm_read(port, rf_reg) & 0xff;
1445 static int msm_poll_get_char_dm(struct uart_port *port)
1450 unsigned char *sp = (unsigned char *)&slop;
1452 /* Check if a previous read had more than one char */
1454 c = sp[sizeof(slop) - count];
1456 /* Or if FIFO is empty */
1457 } else if (!(msm_read(port, MSM_UART_SR) & MSM_UART_SR_RX_READY)) {
1459 * If RX packing buffer has less than a word, force stale to
1460 * push contents into RX FIFO
1462 count = msm_read(port, UARTDM_RXFS);
1463 count = (count >> UARTDM_RXFS_BUF_SHIFT) & UARTDM_RXFS_BUF_MASK;
1465 msm_write(port, MSM_UART_CR_CMD_FORCE_STALE, MSM_UART_CR);
1466 slop = msm_read(port, UARTDM_RF);
1469 msm_write(port, MSM_UART_CR_CMD_RESET_STALE_INT, MSM_UART_CR);
1470 msm_write(port, 0xFFFFFF, UARTDM_DMRX);
1471 msm_write(port, MSM_UART_CR_CMD_STALE_EVENT_ENABLE, MSM_UART_CR);
1475 /* FIFO has a word */
1477 slop = msm_read(port, UARTDM_RF);
1479 count = sizeof(slop) - 1;
1485 static int msm_poll_get_char(struct uart_port *port)
1489 struct msm_port *msm_port = to_msm_port(port);
1491 /* Disable all interrupts */
1492 imr = msm_read(port, MSM_UART_IMR);
1493 msm_write(port, 0, MSM_UART_IMR);
1495 if (msm_port->is_uartdm)
1496 c = msm_poll_get_char_dm(port);
1498 c = msm_poll_get_char_single(port);
1500 /* Enable interrupts */
1501 msm_write(port, imr, MSM_UART_IMR);
1506 static void msm_poll_put_char(struct uart_port *port, unsigned char c)
1509 struct msm_port *msm_port = to_msm_port(port);
1511 /* Disable all interrupts */
1512 imr = msm_read(port, MSM_UART_IMR);
1513 msm_write(port, 0, MSM_UART_IMR);
1515 if (msm_port->is_uartdm)
1516 msm_reset_dm_count(port, 1);
1518 /* Wait until FIFO is empty */
1519 while (!(msm_read(port, MSM_UART_SR) & MSM_UART_SR_TX_READY))
1522 /* Write a character */
1523 msm_write(port, c, msm_port->is_uartdm ? UARTDM_TF : MSM_UART_TF);
1525 /* Wait until FIFO is empty */
1526 while (!(msm_read(port, MSM_UART_SR) & MSM_UART_SR_TX_READY))
1529 /* Enable interrupts */
1530 msm_write(port, imr, MSM_UART_IMR);
1534 static const struct uart_ops msm_uart_pops = {
1535 .tx_empty = msm_tx_empty,
1536 .set_mctrl = msm_set_mctrl,
1537 .get_mctrl = msm_get_mctrl,
1538 .stop_tx = msm_stop_tx,
1539 .start_tx = msm_start_tx,
1540 .stop_rx = msm_stop_rx,
1541 .enable_ms = msm_enable_ms,
1542 .break_ctl = msm_break_ctl,
1543 .startup = msm_startup,
1544 .shutdown = msm_shutdown,
1545 .set_termios = msm_set_termios,
1547 .release_port = msm_release_port,
1548 .request_port = msm_request_port,
1549 .config_port = msm_config_port,
1550 .verify_port = msm_verify_port,
1552 #ifdef CONFIG_CONSOLE_POLL
1553 .poll_get_char = msm_poll_get_char,
1554 .poll_put_char = msm_poll_put_char,
1558 static struct msm_port msm_uart_ports[] = {
1562 .ops = &msm_uart_pops,
1563 .flags = UPF_BOOT_AUTOCONF,
1571 .ops = &msm_uart_pops,
1572 .flags = UPF_BOOT_AUTOCONF,
1580 .ops = &msm_uart_pops,
1581 .flags = UPF_BOOT_AUTOCONF,
1588 #define MSM_UART_NR ARRAY_SIZE(msm_uart_ports)
1590 static inline struct uart_port *msm_get_port_from_line(unsigned int line)
1592 return &msm_uart_ports[line].uart;
1595 #ifdef CONFIG_SERIAL_MSM_CONSOLE
1596 static void __msm_console_write(struct uart_port *port, const char *s,
1597 unsigned int count, bool is_uartdm)
1599 unsigned long flags;
1601 int num_newlines = 0;
1602 bool replaced = false;
1607 tf = port->membase + UARTDM_TF;
1609 tf = port->membase + MSM_UART_TF;
1611 /* Account for newlines that will get a carriage return added */
1612 for (i = 0; i < count; i++)
1615 count += num_newlines;
1617 if (oops_in_progress)
1618 locked = uart_port_trylock_irqsave(port, &flags);
1620 uart_port_lock_irqsave(port, &flags);
1623 msm_reset_dm_count(port, count);
1628 unsigned int num_chars;
1629 char buf[4] = { 0 };
1632 num_chars = min(count - i, (unsigned int)sizeof(buf));
1636 for (j = 0; j < num_chars; j++) {
1639 if (c == '\n' && !replaced) {
1644 if (j < num_chars) {
1651 while (!(msm_read(port, MSM_UART_SR) & MSM_UART_SR_TX_READY))
1654 iowrite32_rep(tf, buf, 1);
1659 uart_port_unlock_irqrestore(port, flags);
1662 static void msm_console_write(struct console *co, const char *s,
1665 struct uart_port *port;
1666 struct msm_port *msm_port;
1668 BUG_ON(co->index < 0 || co->index >= MSM_UART_NR);
1670 port = msm_get_port_from_line(co->index);
1671 msm_port = to_msm_port(port);
1673 __msm_console_write(port, s, count, msm_port->is_uartdm);
1676 static int msm_console_setup(struct console *co, char *options)
1678 struct uart_port *port;
1684 if (unlikely(co->index >= MSM_UART_NR || co->index < 0))
1687 port = msm_get_port_from_line(co->index);
1689 if (unlikely(!port->membase))
1692 msm_init_clock(port);
1695 uart_parse_options(options, &baud, &parity, &bits, &flow);
1697 pr_info("msm_serial: console setup on port #%d\n", port->line);
1699 return uart_set_options(port, co, baud, parity, bits, flow);
1703 msm_serial_early_write(struct console *con, const char *s, unsigned n)
1705 struct earlycon_device *dev = con->data;
1707 __msm_console_write(&dev->port, s, n, false);
1711 msm_serial_early_console_setup(struct earlycon_device *device, const char *opt)
1713 if (!device->port.membase)
1716 device->con->write = msm_serial_early_write;
1719 OF_EARLYCON_DECLARE(msm_serial, "qcom,msm-uart",
1720 msm_serial_early_console_setup);
1723 msm_serial_early_write_dm(struct console *con, const char *s, unsigned n)
1725 struct earlycon_device *dev = con->data;
1727 __msm_console_write(&dev->port, s, n, true);
1731 msm_serial_early_console_setup_dm(struct earlycon_device *device,
1734 if (!device->port.membase)
1737 device->con->write = msm_serial_early_write_dm;
1740 OF_EARLYCON_DECLARE(msm_serial_dm, "qcom,msm-uartdm",
1741 msm_serial_early_console_setup_dm);
1743 static struct uart_driver msm_uart_driver;
1745 static struct console msm_console = {
1747 .write = msm_console_write,
1748 .device = uart_console_device,
1749 .setup = msm_console_setup,
1750 .flags = CON_PRINTBUFFER,
1752 .data = &msm_uart_driver,
1755 #define MSM_CONSOLE (&msm_console)
1758 #define MSM_CONSOLE NULL
1761 static struct uart_driver msm_uart_driver = {
1762 .owner = THIS_MODULE,
1763 .driver_name = "msm_serial",
1764 .dev_name = "ttyMSM",
1766 .cons = MSM_CONSOLE,
1769 static atomic_t msm_uart_next_id = ATOMIC_INIT(0);
1771 static const struct of_device_id msm_uartdm_table[] = {
1772 { .compatible = "qcom,msm-uartdm-v1.1", .data = (void *)UARTDM_1P1 },
1773 { .compatible = "qcom,msm-uartdm-v1.2", .data = (void *)UARTDM_1P2 },
1774 { .compatible = "qcom,msm-uartdm-v1.3", .data = (void *)UARTDM_1P3 },
1775 { .compatible = "qcom,msm-uartdm-v1.4", .data = (void *)UARTDM_1P4 },
1779 static int msm_serial_probe(struct platform_device *pdev)
1781 struct msm_port *msm_port;
1782 struct resource *resource;
1783 struct uart_port *port;
1784 const struct of_device_id *id;
1787 if (pdev->dev.of_node)
1788 line = of_alias_get_id(pdev->dev.of_node, "serial");
1793 line = atomic_inc_return(&msm_uart_next_id) - 1;
1795 if (unlikely(line < 0 || line >= MSM_UART_NR))
1798 dev_info(&pdev->dev, "msm_serial: detected port #%d\n", line);
1800 port = msm_get_port_from_line(line);
1801 port->dev = &pdev->dev;
1802 msm_port = to_msm_port(port);
1804 id = of_match_device(msm_uartdm_table, &pdev->dev);
1806 msm_port->is_uartdm = (unsigned long)id->data;
1808 msm_port->is_uartdm = 0;
1810 msm_port->clk = devm_clk_get(&pdev->dev, "core");
1811 if (IS_ERR(msm_port->clk))
1812 return PTR_ERR(msm_port->clk);
1814 if (msm_port->is_uartdm) {
1815 msm_port->pclk = devm_clk_get(&pdev->dev, "iface");
1816 if (IS_ERR(msm_port->pclk))
1817 return PTR_ERR(msm_port->pclk);
1820 ret = devm_pm_opp_set_clkname(&pdev->dev, "core");
1824 /* OPP table is optional */
1825 ret = devm_pm_opp_of_add_table(&pdev->dev);
1826 if (ret && ret != -ENODEV)
1827 return dev_err_probe(&pdev->dev, ret, "invalid OPP table\n");
1829 port->uartclk = clk_get_rate(msm_port->clk);
1830 dev_info(&pdev->dev, "uartclk = %d\n", port->uartclk);
1832 resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1833 if (unlikely(!resource))
1835 port->mapbase = resource->start;
1837 irq = platform_get_irq(pdev, 0);
1838 if (unlikely(irq < 0))
1841 port->has_sysrq = IS_ENABLED(CONFIG_SERIAL_MSM_CONSOLE);
1843 platform_set_drvdata(pdev, port);
1845 return uart_add_one_port(&msm_uart_driver, port);
1848 static void msm_serial_remove(struct platform_device *pdev)
1850 struct uart_port *port = platform_get_drvdata(pdev);
1852 uart_remove_one_port(&msm_uart_driver, port);
1855 static const struct of_device_id msm_match_table[] = {
1856 { .compatible = "qcom,msm-uart" },
1857 { .compatible = "qcom,msm-uartdm" },
1860 MODULE_DEVICE_TABLE(of, msm_match_table);
1862 static int __maybe_unused msm_serial_suspend(struct device *dev)
1864 struct msm_port *port = dev_get_drvdata(dev);
1866 uart_suspend_port(&msm_uart_driver, &port->uart);
1871 static int __maybe_unused msm_serial_resume(struct device *dev)
1873 struct msm_port *port = dev_get_drvdata(dev);
1875 uart_resume_port(&msm_uart_driver, &port->uart);
1880 static const struct dev_pm_ops msm_serial_dev_pm_ops = {
1881 SET_SYSTEM_SLEEP_PM_OPS(msm_serial_suspend, msm_serial_resume)
1884 static struct platform_driver msm_platform_driver = {
1885 .remove_new = msm_serial_remove,
1886 .probe = msm_serial_probe,
1888 .name = "msm_serial",
1889 .pm = &msm_serial_dev_pm_ops,
1890 .of_match_table = msm_match_table,
1894 static int __init msm_serial_init(void)
1898 ret = uart_register_driver(&msm_uart_driver);
1902 ret = platform_driver_register(&msm_platform_driver);
1904 uart_unregister_driver(&msm_uart_driver);
1906 pr_info("msm_serial: driver initialized\n");
1911 static void __exit msm_serial_exit(void)
1913 platform_driver_unregister(&msm_platform_driver);
1914 uart_unregister_driver(&msm_uart_driver);
1917 module_init(msm_serial_init);
1918 module_exit(msm_serial_exit);
1920 MODULE_AUTHOR("Robert Love <rlove@google.com>");
1921 MODULE_DESCRIPTION("Driver for msm7x serial device");
1922 MODULE_LICENSE("GPL");