1 // SPDX-License-Identifier: GPL-2.0
3 * Driver for msm7k serial device and console
5 * Copyright (C) 2007 Google, Inc.
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/delay.h>
29 #include <linux/of_device.h>
30 #include <linux/wait.h>
32 #define MSM_UART_MR1 0x0000
34 #define MSM_UART_MR1_AUTO_RFR_LEVEL0 0x3F
35 #define MSM_UART_MR1_AUTO_RFR_LEVEL1 0x3FF00
36 #define MSM_UART_DM_MR1_AUTO_RFR_LEVEL1 0xFFFFFF00
37 #define MSM_UART_MR1_RX_RDY_CTL BIT(7)
38 #define MSM_UART_MR1_CTS_CTL BIT(6)
40 #define MSM_UART_MR2 0x0004
41 #define MSM_UART_MR2_ERROR_MODE BIT(6)
42 #define MSM_UART_MR2_BITS_PER_CHAR 0x30
43 #define MSM_UART_MR2_BITS_PER_CHAR_5 (0x0 << 4)
44 #define MSM_UART_MR2_BITS_PER_CHAR_6 (0x1 << 4)
45 #define MSM_UART_MR2_BITS_PER_CHAR_7 (0x2 << 4)
46 #define MSM_UART_MR2_BITS_PER_CHAR_8 (0x3 << 4)
47 #define MSM_UART_MR2_STOP_BIT_LEN_ONE (0x1 << 2)
48 #define MSM_UART_MR2_STOP_BIT_LEN_TWO (0x3 << 2)
49 #define MSM_UART_MR2_PARITY_MODE_NONE 0x0
50 #define MSM_UART_MR2_PARITY_MODE_ODD 0x1
51 #define MSM_UART_MR2_PARITY_MODE_EVEN 0x2
52 #define MSM_UART_MR2_PARITY_MODE_SPACE 0x3
53 #define MSM_UART_MR2_PARITY_MODE 0x3
55 #define MSM_UART_CSR 0x0008
57 #define MSM_UART_TF 0x000C
58 #define UARTDM_TF 0x0070
60 #define MSM_UART_CR 0x0010
61 #define MSM_UART_CR_CMD_NULL (0 << 4)
62 #define MSM_UART_CR_CMD_RESET_RX (1 << 4)
63 #define MSM_UART_CR_CMD_RESET_TX (2 << 4)
64 #define MSM_UART_CR_CMD_RESET_ERR (3 << 4)
65 #define MSM_UART_CR_CMD_RESET_BREAK_INT (4 << 4)
66 #define MSM_UART_CR_CMD_START_BREAK (5 << 4)
67 #define MSM_UART_CR_CMD_STOP_BREAK (6 << 4)
68 #define MSM_UART_CR_CMD_RESET_CTS (7 << 4)
69 #define MSM_UART_CR_CMD_RESET_STALE_INT (8 << 4)
70 #define MSM_UART_CR_CMD_PACKET_MODE (9 << 4)
71 #define MSM_UART_CR_CMD_MODE_RESET (12 << 4)
72 #define MSM_UART_CR_CMD_SET_RFR (13 << 4)
73 #define MSM_UART_CR_CMD_RESET_RFR (14 << 4)
74 #define MSM_UART_CR_CMD_PROTECTION_EN (16 << 4)
75 #define MSM_UART_CR_CMD_STALE_EVENT_DISABLE (6 << 8)
76 #define MSM_UART_CR_CMD_STALE_EVENT_ENABLE (80 << 4)
77 #define MSM_UART_CR_CMD_FORCE_STALE (4 << 8)
78 #define MSM_UART_CR_CMD_RESET_TX_READY (3 << 8)
79 #define MSM_UART_CR_TX_DISABLE BIT(3)
80 #define MSM_UART_CR_TX_ENABLE BIT(2)
81 #define MSM_UART_CR_RX_DISABLE BIT(1)
82 #define MSM_UART_CR_RX_ENABLE BIT(0)
83 #define MSM_UART_CR_CMD_RESET_RXBREAK_START ((1 << 11) | (2 << 4))
85 #define MSM_UART_IMR 0x0014
86 #define MSM_UART_IMR_TXLEV BIT(0)
87 #define MSM_UART_IMR_RXSTALE BIT(3)
88 #define MSM_UART_IMR_RXLEV BIT(4)
89 #define MSM_UART_IMR_DELTA_CTS BIT(5)
90 #define MSM_UART_IMR_CURRENT_CTS BIT(6)
91 #define MSM_UART_IMR_RXBREAK_START BIT(10)
93 #define MSM_UART_IPR_RXSTALE_LAST 0x20
94 #define MSM_UART_IPR_STALE_LSB 0x1F
95 #define MSM_UART_IPR_STALE_TIMEOUT_MSB 0x3FF80
96 #define MSM_UART_DM_IPR_STALE_TIMEOUT_MSB 0xFFFFFF80
98 #define MSM_UART_IPR 0x0018
99 #define MSM_UART_TFWR 0x001C
100 #define MSM_UART_RFWR 0x0020
101 #define MSM_UART_HCR 0x0024
103 #define MSM_UART_MREG 0x0028
104 #define MSM_UART_NREG 0x002C
105 #define MSM_UART_DREG 0x0030
106 #define MSM_UART_MNDREG 0x0034
107 #define MSM_UART_IRDA 0x0038
108 #define MSM_UART_MISR_MODE 0x0040
109 #define MSM_UART_MISR_RESET 0x0044
110 #define MSM_UART_MISR_EXPORT 0x0048
111 #define MSM_UART_MISR_VAL 0x004C
112 #define MSM_UART_TEST_CTRL 0x0050
114 #define MSM_UART_SR 0x0008
115 #define MSM_UART_SR_HUNT_CHAR BIT(7)
116 #define MSM_UART_SR_RX_BREAK BIT(6)
117 #define MSM_UART_SR_PAR_FRAME_ERR BIT(5)
118 #define MSM_UART_SR_OVERRUN BIT(4)
119 #define MSM_UART_SR_TX_EMPTY BIT(3)
120 #define MSM_UART_SR_TX_READY BIT(2)
121 #define MSM_UART_SR_RX_FULL BIT(1)
122 #define MSM_UART_SR_RX_READY BIT(0)
124 #define MSM_UART_RF 0x000C
125 #define UARTDM_RF 0x0070
126 #define MSM_UART_MISR 0x0010
127 #define MSM_UART_ISR 0x0014
128 #define MSM_UART_ISR_TX_READY BIT(7)
130 #define UARTDM_RXFS 0x50
131 #define UARTDM_RXFS_BUF_SHIFT 0x7
132 #define UARTDM_RXFS_BUF_MASK 0x7
134 #define UARTDM_DMEN 0x3C
135 #define UARTDM_DMEN_RX_SC_ENABLE BIT(5)
136 #define UARTDM_DMEN_TX_SC_ENABLE BIT(4)
138 #define UARTDM_DMEN_TX_BAM_ENABLE BIT(2) /* UARTDM_1P4 */
139 #define UARTDM_DMEN_TX_DM_ENABLE BIT(0) /* < UARTDM_1P4 */
141 #define UARTDM_DMEN_RX_BAM_ENABLE BIT(3) /* UARTDM_1P4 */
142 #define UARTDM_DMEN_RX_DM_ENABLE BIT(1) /* < UARTDM_1P4 */
144 #define UARTDM_DMRX 0x34
145 #define UARTDM_NCF_TX 0x40
146 #define UARTDM_RX_TOTAL_SNAP 0x38
148 #define UARTDM_BURST_SIZE 16 /* in bytes */
149 #define UARTDM_TX_AIGN(x) ((x) & ~0x3) /* valid for > 1p3 */
150 #define UARTDM_TX_MAX 256 /* in bytes, valid for <= 1p3 */
151 #define UARTDM_RX_SIZE (UART_XMIT_SIZE / 4)
161 struct dma_chan *chan;
162 enum dma_data_direction dir;
168 struct dma_async_tx_descriptor *desc;
172 struct uart_port uart;
178 unsigned int old_snap_state;
180 struct msm_dma tx_dma;
181 struct msm_dma rx_dma;
184 static inline struct msm_port *to_msm_port(struct uart_port *up)
186 return container_of(up, struct msm_port, uart);
190 void msm_write(struct uart_port *port, unsigned int val, unsigned int off)
192 writel_relaxed(val, port->membase + off);
196 unsigned int msm_read(struct uart_port *port, unsigned int off)
198 return readl_relaxed(port->membase + off);
202 * Setup the MND registers to use the TCXO clock.
204 static void msm_serial_set_mnd_regs_tcxo(struct uart_port *port)
206 msm_write(port, 0x06, MSM_UART_MREG);
207 msm_write(port, 0xF1, MSM_UART_NREG);
208 msm_write(port, 0x0F, MSM_UART_DREG);
209 msm_write(port, 0x1A, MSM_UART_MNDREG);
210 port->uartclk = 1843200;
214 * Setup the MND registers to use the TCXO clock divided by 4.
216 static void msm_serial_set_mnd_regs_tcxoby4(struct uart_port *port)
218 msm_write(port, 0x18, MSM_UART_MREG);
219 msm_write(port, 0xF6, MSM_UART_NREG);
220 msm_write(port, 0x0F, MSM_UART_DREG);
221 msm_write(port, 0x0A, MSM_UART_MNDREG);
222 port->uartclk = 1843200;
225 static void msm_serial_set_mnd_regs(struct uart_port *port)
227 struct msm_port *msm_port = to_msm_port(port);
230 * These registers don't exist so we change the clk input rate
231 * on uartdm hardware instead
233 if (msm_port->is_uartdm)
236 if (port->uartclk == 19200000)
237 msm_serial_set_mnd_regs_tcxo(port);
238 else if (port->uartclk == 4800000)
239 msm_serial_set_mnd_regs_tcxoby4(port);
242 static void msm_handle_tx(struct uart_port *port);
243 static void msm_start_rx_dma(struct msm_port *msm_port);
245 static void msm_stop_dma(struct uart_port *port, struct msm_dma *dma)
247 struct device *dev = port->dev;
254 dmaengine_terminate_all(dma->chan);
257 * DMA Stall happens if enqueue and flush command happens concurrently.
258 * For example before changing the baud rate/protocol configuration and
259 * sending flush command to ADM, disable the channel of UARTDM.
260 * Note: should not reset the receiver here immediately as it is not
261 * suggested to do disable/reset or reset/disable at the same time.
263 val = msm_read(port, UARTDM_DMEN);
264 val &= ~dma->enable_bit;
265 msm_write(port, val, UARTDM_DMEN);
268 dma_unmap_single(dev, dma->phys, mapped, dma->dir);
271 static void msm_release_dma(struct msm_port *msm_port)
275 dma = &msm_port->tx_dma;
277 msm_stop_dma(&msm_port->uart, dma);
278 dma_release_channel(dma->chan);
281 memset(dma, 0, sizeof(*dma));
283 dma = &msm_port->rx_dma;
285 msm_stop_dma(&msm_port->uart, dma);
286 dma_release_channel(dma->chan);
290 memset(dma, 0, sizeof(*dma));
293 static void msm_request_tx_dma(struct msm_port *msm_port, resource_size_t base)
295 struct device *dev = msm_port->uart.dev;
296 struct dma_slave_config conf;
297 struct qcom_adm_peripheral_config periph_conf = {};
302 dma = &msm_port->tx_dma;
304 /* allocate DMA resources, if available */
305 dma->chan = dma_request_chan(dev, "tx");
306 if (IS_ERR(dma->chan))
309 of_property_read_u32(dev->of_node, "qcom,tx-crci", &crci);
311 memset(&conf, 0, sizeof(conf));
312 conf.direction = DMA_MEM_TO_DEV;
313 conf.device_fc = true;
314 conf.dst_addr = base + UARTDM_TF;
315 conf.dst_maxburst = UARTDM_BURST_SIZE;
317 conf.peripheral_config = &periph_conf;
318 conf.peripheral_size = sizeof(periph_conf);
319 periph_conf.crci = crci;
322 ret = dmaengine_slave_config(dma->chan, &conf);
326 dma->dir = DMA_TO_DEVICE;
328 if (msm_port->is_uartdm < UARTDM_1P4)
329 dma->enable_bit = UARTDM_DMEN_TX_DM_ENABLE;
331 dma->enable_bit = UARTDM_DMEN_TX_BAM_ENABLE;
336 dma_release_channel(dma->chan);
338 memset(dma, 0, sizeof(*dma));
341 static void msm_request_rx_dma(struct msm_port *msm_port, resource_size_t base)
343 struct device *dev = msm_port->uart.dev;
344 struct dma_slave_config conf;
345 struct qcom_adm_peripheral_config periph_conf = {};
350 dma = &msm_port->rx_dma;
352 /* allocate DMA resources, if available */
353 dma->chan = dma_request_chan(dev, "rx");
354 if (IS_ERR(dma->chan))
357 of_property_read_u32(dev->of_node, "qcom,rx-crci", &crci);
359 dma->virt = kzalloc(UARTDM_RX_SIZE, GFP_KERNEL);
363 memset(&conf, 0, sizeof(conf));
364 conf.direction = DMA_DEV_TO_MEM;
365 conf.device_fc = true;
366 conf.src_addr = base + UARTDM_RF;
367 conf.src_maxburst = UARTDM_BURST_SIZE;
369 conf.peripheral_config = &periph_conf;
370 conf.peripheral_size = sizeof(periph_conf);
371 periph_conf.crci = crci;
374 ret = dmaengine_slave_config(dma->chan, &conf);
378 dma->dir = DMA_FROM_DEVICE;
380 if (msm_port->is_uartdm < UARTDM_1P4)
381 dma->enable_bit = UARTDM_DMEN_RX_DM_ENABLE;
383 dma->enable_bit = UARTDM_DMEN_RX_BAM_ENABLE;
389 dma_release_channel(dma->chan);
391 memset(dma, 0, sizeof(*dma));
394 static inline void msm_wait_for_xmitr(struct uart_port *port)
396 unsigned int timeout = 500000;
398 while (!(msm_read(port, MSM_UART_SR) & MSM_UART_SR_TX_EMPTY)) {
399 if (msm_read(port, MSM_UART_ISR) & MSM_UART_ISR_TX_READY)
405 msm_write(port, MSM_UART_CR_CMD_RESET_TX_READY, MSM_UART_CR);
408 static void msm_stop_tx(struct uart_port *port)
410 struct msm_port *msm_port = to_msm_port(port);
412 msm_port->imr &= ~MSM_UART_IMR_TXLEV;
413 msm_write(port, msm_port->imr, MSM_UART_IMR);
416 static void msm_start_tx(struct uart_port *port)
418 struct msm_port *msm_port = to_msm_port(port);
419 struct msm_dma *dma = &msm_port->tx_dma;
421 /* Already started in DMA mode */
425 msm_port->imr |= MSM_UART_IMR_TXLEV;
426 msm_write(port, msm_port->imr, MSM_UART_IMR);
429 static void msm_reset_dm_count(struct uart_port *port, int count)
431 msm_wait_for_xmitr(port);
432 msm_write(port, count, UARTDM_NCF_TX);
433 msm_read(port, UARTDM_NCF_TX);
436 static void msm_complete_tx_dma(void *args)
438 struct msm_port *msm_port = args;
439 struct uart_port *port = &msm_port->uart;
440 struct circ_buf *xmit = &port->state->xmit;
441 struct msm_dma *dma = &msm_port->tx_dma;
442 struct dma_tx_state state;
447 uart_port_lock_irqsave(port, &flags);
449 /* Already stopped */
453 dmaengine_tx_status(dma->chan, dma->cookie, &state);
455 dma_unmap_single(port->dev, dma->phys, dma->count, dma->dir);
457 val = msm_read(port, UARTDM_DMEN);
458 val &= ~dma->enable_bit;
459 msm_write(port, val, UARTDM_DMEN);
461 if (msm_port->is_uartdm > UARTDM_1P3) {
462 msm_write(port, MSM_UART_CR_CMD_RESET_TX, MSM_UART_CR);
463 msm_write(port, MSM_UART_CR_TX_ENABLE, MSM_UART_CR);
466 count = dma->count - state.residue;
467 uart_xmit_advance(port, count);
470 /* Restore "Tx FIFO below watermark" interrupt */
471 msm_port->imr |= MSM_UART_IMR_TXLEV;
472 msm_write(port, msm_port->imr, MSM_UART_IMR);
474 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
475 uart_write_wakeup(port);
479 uart_port_unlock_irqrestore(port, flags);
482 static int msm_handle_tx_dma(struct msm_port *msm_port, unsigned int count)
484 struct circ_buf *xmit = &msm_port->uart.state->xmit;
485 struct uart_port *port = &msm_port->uart;
486 struct msm_dma *dma = &msm_port->tx_dma;
491 cpu_addr = &xmit->buf[xmit->tail];
493 dma->phys = dma_map_single(port->dev, cpu_addr, count, dma->dir);
494 ret = dma_mapping_error(port->dev, dma->phys);
498 dma->desc = dmaengine_prep_slave_single(dma->chan, dma->phys,
499 count, DMA_MEM_TO_DEV,
507 dma->desc->callback = msm_complete_tx_dma;
508 dma->desc->callback_param = msm_port;
510 dma->cookie = dmaengine_submit(dma->desc);
511 ret = dma_submit_error(dma->cookie);
516 * Using DMA complete for Tx FIFO reload, no need for
517 * "Tx FIFO below watermark" one, disable it
519 msm_port->imr &= ~MSM_UART_IMR_TXLEV;
520 msm_write(port, msm_port->imr, MSM_UART_IMR);
524 val = msm_read(port, UARTDM_DMEN);
525 val |= dma->enable_bit;
527 if (msm_port->is_uartdm < UARTDM_1P4)
528 msm_write(port, val, UARTDM_DMEN);
530 msm_reset_dm_count(port, count);
532 if (msm_port->is_uartdm > UARTDM_1P3)
533 msm_write(port, val, UARTDM_DMEN);
535 dma_async_issue_pending(dma->chan);
538 dma_unmap_single(port->dev, dma->phys, count, dma->dir);
542 static void msm_complete_rx_dma(void *args)
544 struct msm_port *msm_port = args;
545 struct uart_port *port = &msm_port->uart;
546 struct tty_port *tport = &port->state->port;
547 struct msm_dma *dma = &msm_port->rx_dma;
548 int count = 0, i, sysrq;
552 uart_port_lock_irqsave(port, &flags);
554 /* Already stopped */
558 val = msm_read(port, UARTDM_DMEN);
559 val &= ~dma->enable_bit;
560 msm_write(port, val, UARTDM_DMEN);
562 if (msm_read(port, MSM_UART_SR) & MSM_UART_SR_OVERRUN) {
563 port->icount.overrun++;
564 tty_insert_flip_char(tport, 0, TTY_OVERRUN);
565 msm_write(port, MSM_UART_CR_CMD_RESET_ERR, MSM_UART_CR);
568 count = msm_read(port, UARTDM_RX_TOTAL_SNAP);
570 port->icount.rx += count;
574 dma_unmap_single(port->dev, dma->phys, UARTDM_RX_SIZE, dma->dir);
576 for (i = 0; i < count; i++) {
577 char flag = TTY_NORMAL;
579 if (msm_port->break_detected && dma->virt[i] == 0) {
582 msm_port->break_detected = false;
583 if (uart_handle_break(port))
587 if (!(port->read_status_mask & MSM_UART_SR_RX_BREAK))
590 uart_port_unlock_irqrestore(port, flags);
591 sysrq = uart_handle_sysrq_char(port, dma->virt[i]);
592 uart_port_lock_irqsave(port, &flags);
594 tty_insert_flip_char(tport, dma->virt[i], flag);
597 msm_start_rx_dma(msm_port);
599 uart_port_unlock_irqrestore(port, flags);
602 tty_flip_buffer_push(tport);
605 static void msm_start_rx_dma(struct msm_port *msm_port)
607 struct msm_dma *dma = &msm_port->rx_dma;
608 struct uart_port *uart = &msm_port->uart;
612 if (IS_ENABLED(CONFIG_CONSOLE_POLL))
618 dma->phys = dma_map_single(uart->dev, dma->virt,
619 UARTDM_RX_SIZE, dma->dir);
620 ret = dma_mapping_error(uart->dev, dma->phys);
624 dma->desc = dmaengine_prep_slave_single(dma->chan, dma->phys,
625 UARTDM_RX_SIZE, DMA_DEV_TO_MEM,
630 dma->desc->callback = msm_complete_rx_dma;
631 dma->desc->callback_param = msm_port;
633 dma->cookie = dmaengine_submit(dma->desc);
634 ret = dma_submit_error(dma->cookie);
638 * Using DMA for FIFO off-load, no need for "Rx FIFO over
639 * watermark" or "stale" interrupts, disable them
641 msm_port->imr &= ~(MSM_UART_IMR_RXLEV | MSM_UART_IMR_RXSTALE);
644 * Well, when DMA is ADM3 engine(implied by <= UARTDM v1.3),
645 * we need RXSTALE to flush input DMA fifo to memory
647 if (msm_port->is_uartdm < UARTDM_1P4)
648 msm_port->imr |= MSM_UART_IMR_RXSTALE;
650 msm_write(uart, msm_port->imr, MSM_UART_IMR);
652 dma->count = UARTDM_RX_SIZE;
654 dma_async_issue_pending(dma->chan);
656 msm_write(uart, MSM_UART_CR_CMD_RESET_STALE_INT, MSM_UART_CR);
657 msm_write(uart, MSM_UART_CR_CMD_STALE_EVENT_ENABLE, MSM_UART_CR);
659 val = msm_read(uart, UARTDM_DMEN);
660 val |= dma->enable_bit;
662 if (msm_port->is_uartdm < UARTDM_1P4)
663 msm_write(uart, val, UARTDM_DMEN);
665 msm_write(uart, UARTDM_RX_SIZE, UARTDM_DMRX);
667 if (msm_port->is_uartdm > UARTDM_1P3)
668 msm_write(uart, val, UARTDM_DMEN);
672 dma_unmap_single(uart->dev, dma->phys, UARTDM_RX_SIZE, dma->dir);
676 * Switch from DMA to SW/FIFO mode. After clearing Rx BAM (UARTDM_DMEN),
677 * receiver must be reset.
679 msm_write(uart, MSM_UART_CR_CMD_RESET_RX, MSM_UART_CR);
680 msm_write(uart, MSM_UART_CR_RX_ENABLE, MSM_UART_CR);
682 msm_write(uart, MSM_UART_CR_CMD_RESET_STALE_INT, MSM_UART_CR);
683 msm_write(uart, 0xFFFFFF, UARTDM_DMRX);
684 msm_write(uart, MSM_UART_CR_CMD_STALE_EVENT_ENABLE, MSM_UART_CR);
686 /* Re-enable RX interrupts */
687 msm_port->imr |= MSM_UART_IMR_RXLEV | MSM_UART_IMR_RXSTALE;
688 msm_write(uart, msm_port->imr, MSM_UART_IMR);
691 static void msm_stop_rx(struct uart_port *port)
693 struct msm_port *msm_port = to_msm_port(port);
694 struct msm_dma *dma = &msm_port->rx_dma;
696 msm_port->imr &= ~(MSM_UART_IMR_RXLEV | MSM_UART_IMR_RXSTALE);
697 msm_write(port, msm_port->imr, MSM_UART_IMR);
700 msm_stop_dma(port, dma);
703 static void msm_enable_ms(struct uart_port *port)
705 struct msm_port *msm_port = to_msm_port(port);
707 msm_port->imr |= MSM_UART_IMR_DELTA_CTS;
708 msm_write(port, msm_port->imr, MSM_UART_IMR);
711 static void msm_handle_rx_dm(struct uart_port *port, unsigned int misr)
712 __must_hold(&port->lock)
714 struct tty_port *tport = &port->state->port;
717 struct msm_port *msm_port = to_msm_port(port);
719 if ((msm_read(port, MSM_UART_SR) & MSM_UART_SR_OVERRUN)) {
720 port->icount.overrun++;
721 tty_insert_flip_char(tport, 0, TTY_OVERRUN);
722 msm_write(port, MSM_UART_CR_CMD_RESET_ERR, MSM_UART_CR);
725 if (misr & MSM_UART_IMR_RXSTALE) {
726 count = msm_read(port, UARTDM_RX_TOTAL_SNAP) -
727 msm_port->old_snap_state;
728 msm_port->old_snap_state = 0;
730 count = 4 * (msm_read(port, MSM_UART_RFWR));
731 msm_port->old_snap_state += count;
734 /* TODO: Precise error reporting */
736 port->icount.rx += count;
739 unsigned char buf[4];
740 int sysrq, r_count, i;
742 sr = msm_read(port, MSM_UART_SR);
743 if ((sr & MSM_UART_SR_RX_READY) == 0) {
744 msm_port->old_snap_state -= count;
748 ioread32_rep(port->membase + UARTDM_RF, buf, 1);
749 r_count = min_t(int, count, sizeof(buf));
751 for (i = 0; i < r_count; i++) {
752 char flag = TTY_NORMAL;
754 if (msm_port->break_detected && buf[i] == 0) {
757 msm_port->break_detected = false;
758 if (uart_handle_break(port))
762 if (!(port->read_status_mask & MSM_UART_SR_RX_BREAK))
765 uart_port_unlock(port);
766 sysrq = uart_handle_sysrq_char(port, buf[i]);
767 uart_port_lock(port);
769 tty_insert_flip_char(tport, buf[i], flag);
774 tty_flip_buffer_push(tport);
776 if (misr & (MSM_UART_IMR_RXSTALE))
777 msm_write(port, MSM_UART_CR_CMD_RESET_STALE_INT, MSM_UART_CR);
778 msm_write(port, 0xFFFFFF, UARTDM_DMRX);
779 msm_write(port, MSM_UART_CR_CMD_STALE_EVENT_ENABLE, MSM_UART_CR);
782 msm_start_rx_dma(msm_port);
785 static void msm_handle_rx(struct uart_port *port)
786 __must_hold(&port->lock)
788 struct tty_port *tport = &port->state->port;
792 * Handle overrun. My understanding of the hardware is that overrun
793 * is not tied to the RX buffer, so we handle the case out of band.
795 if ((msm_read(port, MSM_UART_SR) & MSM_UART_SR_OVERRUN)) {
796 port->icount.overrun++;
797 tty_insert_flip_char(tport, 0, TTY_OVERRUN);
798 msm_write(port, MSM_UART_CR_CMD_RESET_ERR, MSM_UART_CR);
801 /* and now the main RX loop */
802 while ((sr = msm_read(port, MSM_UART_SR)) & MSM_UART_SR_RX_READY) {
804 char flag = TTY_NORMAL;
807 c = msm_read(port, MSM_UART_RF);
809 if (sr & MSM_UART_SR_RX_BREAK) {
811 if (uart_handle_break(port))
813 } else if (sr & MSM_UART_SR_PAR_FRAME_ERR) {
814 port->icount.frame++;
819 /* Mask conditions we're ignoring. */
820 sr &= port->read_status_mask;
822 if (sr & MSM_UART_SR_RX_BREAK)
824 else if (sr & MSM_UART_SR_PAR_FRAME_ERR)
827 uart_port_unlock(port);
828 sysrq = uart_handle_sysrq_char(port, c);
829 uart_port_lock(port);
831 tty_insert_flip_char(tport, c, flag);
834 tty_flip_buffer_push(tport);
837 static void msm_handle_tx_pio(struct uart_port *port, unsigned int tx_count)
839 struct circ_buf *xmit = &port->state->xmit;
840 struct msm_port *msm_port = to_msm_port(port);
841 unsigned int num_chars;
842 unsigned int tf_pointer = 0;
845 if (msm_port->is_uartdm)
846 tf = port->membase + UARTDM_TF;
848 tf = port->membase + MSM_UART_TF;
850 if (tx_count && msm_port->is_uartdm)
851 msm_reset_dm_count(port, tx_count);
853 while (tf_pointer < tx_count) {
857 if (!(msm_read(port, MSM_UART_SR) & MSM_UART_SR_TX_READY))
860 if (msm_port->is_uartdm)
861 num_chars = min(tx_count - tf_pointer,
862 (unsigned int)sizeof(buf));
866 for (i = 0; i < num_chars; i++)
867 buf[i] = xmit->buf[xmit->tail + i];
869 iowrite32_rep(tf, buf, 1);
870 uart_xmit_advance(port, num_chars);
871 tf_pointer += num_chars;
874 /* disable tx interrupts if nothing more to send */
875 if (uart_circ_empty(xmit))
878 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
879 uart_write_wakeup(port);
882 static void msm_handle_tx(struct uart_port *port)
884 struct msm_port *msm_port = to_msm_port(port);
885 struct circ_buf *xmit = &msm_port->uart.state->xmit;
886 struct msm_dma *dma = &msm_port->tx_dma;
887 unsigned int pio_count, dma_count, dma_min;
893 if (msm_port->is_uartdm)
894 tf = port->membase + UARTDM_TF;
896 tf = port->membase + MSM_UART_TF;
898 buf[0] = port->x_char;
900 if (msm_port->is_uartdm)
901 msm_reset_dm_count(port, 1);
903 iowrite32_rep(tf, buf, 1);
909 if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
914 pio_count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
915 dma_count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
917 dma_min = 1; /* Always DMA */
918 if (msm_port->is_uartdm > UARTDM_1P3) {
919 dma_count = UARTDM_TX_AIGN(dma_count);
920 dma_min = UARTDM_BURST_SIZE;
922 if (dma_count > UARTDM_TX_MAX)
923 dma_count = UARTDM_TX_MAX;
926 if (pio_count > port->fifosize)
927 pio_count = port->fifosize;
929 if (!dma->chan || dma_count < dma_min)
930 msm_handle_tx_pio(port, pio_count);
932 err = msm_handle_tx_dma(msm_port, dma_count);
934 if (err) /* fall back to PIO mode */
935 msm_handle_tx_pio(port, pio_count);
938 static void msm_handle_delta_cts(struct uart_port *port)
940 msm_write(port, MSM_UART_CR_CMD_RESET_CTS, MSM_UART_CR);
942 wake_up_interruptible(&port->state->port.delta_msr_wait);
945 static irqreturn_t msm_uart_irq(int irq, void *dev_id)
947 struct uart_port *port = dev_id;
948 struct msm_port *msm_port = to_msm_port(port);
949 struct msm_dma *dma = &msm_port->rx_dma;
954 uart_port_lock_irqsave(port, &flags);
955 misr = msm_read(port, MSM_UART_MISR);
956 msm_write(port, 0, MSM_UART_IMR); /* disable interrupt */
958 if (misr & MSM_UART_IMR_RXBREAK_START) {
959 msm_port->break_detected = true;
960 msm_write(port, MSM_UART_CR_CMD_RESET_RXBREAK_START, MSM_UART_CR);
963 if (misr & (MSM_UART_IMR_RXLEV | MSM_UART_IMR_RXSTALE)) {
965 val = MSM_UART_CR_CMD_STALE_EVENT_DISABLE;
966 msm_write(port, val, MSM_UART_CR);
967 val = MSM_UART_CR_CMD_RESET_STALE_INT;
968 msm_write(port, val, MSM_UART_CR);
970 * Flush DMA input fifo to memory, this will also
971 * trigger DMA RX completion
973 dmaengine_terminate_all(dma->chan);
974 } else if (msm_port->is_uartdm) {
975 msm_handle_rx_dm(port, misr);
980 if (misr & MSM_UART_IMR_TXLEV)
982 if (misr & MSM_UART_IMR_DELTA_CTS)
983 msm_handle_delta_cts(port);
985 msm_write(port, msm_port->imr, MSM_UART_IMR); /* restore interrupt */
986 uart_port_unlock_irqrestore(port, flags);
991 static unsigned int msm_tx_empty(struct uart_port *port)
993 return (msm_read(port, MSM_UART_SR) & MSM_UART_SR_TX_EMPTY) ? TIOCSER_TEMT : 0;
996 static unsigned int msm_get_mctrl(struct uart_port *port)
998 return TIOCM_CAR | TIOCM_CTS | TIOCM_DSR | TIOCM_RTS;
1001 static void msm_reset(struct uart_port *port)
1003 struct msm_port *msm_port = to_msm_port(port);
1006 /* reset everything */
1007 msm_write(port, MSM_UART_CR_CMD_RESET_RX, MSM_UART_CR);
1008 msm_write(port, MSM_UART_CR_CMD_RESET_TX, MSM_UART_CR);
1009 msm_write(port, MSM_UART_CR_CMD_RESET_ERR, MSM_UART_CR);
1010 msm_write(port, MSM_UART_CR_CMD_RESET_BREAK_INT, MSM_UART_CR);
1011 msm_write(port, MSM_UART_CR_CMD_RESET_CTS, MSM_UART_CR);
1012 msm_write(port, MSM_UART_CR_CMD_RESET_RFR, MSM_UART_CR);
1013 mr = msm_read(port, MSM_UART_MR1);
1014 mr &= ~MSM_UART_MR1_RX_RDY_CTL;
1015 msm_write(port, mr, MSM_UART_MR1);
1017 /* Disable DM modes */
1018 if (msm_port->is_uartdm)
1019 msm_write(port, 0, UARTDM_DMEN);
1022 static void msm_set_mctrl(struct uart_port *port, unsigned int mctrl)
1026 mr = msm_read(port, MSM_UART_MR1);
1028 if (!(mctrl & TIOCM_RTS)) {
1029 mr &= ~MSM_UART_MR1_RX_RDY_CTL;
1030 msm_write(port, mr, MSM_UART_MR1);
1031 msm_write(port, MSM_UART_CR_CMD_RESET_RFR, MSM_UART_CR);
1033 mr |= MSM_UART_MR1_RX_RDY_CTL;
1034 msm_write(port, mr, MSM_UART_MR1);
1038 static void msm_break_ctl(struct uart_port *port, int break_ctl)
1041 msm_write(port, MSM_UART_CR_CMD_START_BREAK, MSM_UART_CR);
1043 msm_write(port, MSM_UART_CR_CMD_STOP_BREAK, MSM_UART_CR);
1046 struct msm_baud_map {
1052 static const struct msm_baud_map *
1053 msm_find_best_baud(struct uart_port *port, unsigned int baud,
1054 unsigned long *rate)
1056 struct msm_port *msm_port = to_msm_port(port);
1057 unsigned int divisor, result;
1058 unsigned long target, old, best_rate = 0, diff, best_diff = ULONG_MAX;
1059 const struct msm_baud_map *entry, *end, *best;
1060 static const struct msm_baud_map table[] = {
1079 best = table; /* Default to smallest divider */
1080 target = clk_round_rate(msm_port->clk, 16 * baud);
1081 divisor = DIV_ROUND_CLOSEST(target, 16 * baud);
1083 end = table + ARRAY_SIZE(table);
1085 while (entry < end) {
1086 if (entry->divisor <= divisor) {
1087 result = target / entry->divisor / 16;
1088 diff = abs(result - baud);
1090 /* Keep track of best entry */
1091 if (diff < best_diff) {
1099 } else if (entry->divisor > divisor) {
1101 target = clk_round_rate(msm_port->clk, old + 1);
1103 * The rate didn't get any faster so we can't do
1104 * better at dividing it down
1109 /* Start the divisor search over at this new rate */
1111 divisor = DIV_ROUND_CLOSEST(target, 16 * baud);
1121 static int msm_set_baud_rate(struct uart_port *port, unsigned int baud,
1122 unsigned long *saved_flags)
1123 __must_hold(&port->lock)
1125 unsigned int rxstale, watermark, mask;
1126 struct msm_port *msm_port = to_msm_port(port);
1127 const struct msm_baud_map *entry;
1128 unsigned long flags, rate;
1130 flags = *saved_flags;
1131 uart_port_unlock_irqrestore(port, flags);
1133 entry = msm_find_best_baud(port, baud, &rate);
1134 clk_set_rate(msm_port->clk, rate);
1135 baud = rate / 16 / entry->divisor;
1137 uart_port_lock_irqsave(port, &flags);
1138 *saved_flags = flags;
1139 port->uartclk = rate;
1141 msm_write(port, entry->code, MSM_UART_CSR);
1143 /* RX stale watermark */
1144 rxstale = entry->rxstale;
1145 watermark = MSM_UART_IPR_STALE_LSB & rxstale;
1146 if (msm_port->is_uartdm) {
1147 mask = MSM_UART_DM_IPR_STALE_TIMEOUT_MSB;
1149 watermark |= MSM_UART_IPR_RXSTALE_LAST;
1150 mask = MSM_UART_IPR_STALE_TIMEOUT_MSB;
1153 watermark |= mask & (rxstale << 2);
1155 msm_write(port, watermark, MSM_UART_IPR);
1157 /* set RX watermark */
1158 watermark = (port->fifosize * 3) / 4;
1159 msm_write(port, watermark, MSM_UART_RFWR);
1161 /* set TX watermark */
1162 msm_write(port, 10, MSM_UART_TFWR);
1164 msm_write(port, MSM_UART_CR_CMD_PROTECTION_EN, MSM_UART_CR);
1167 /* Enable RX and TX */
1168 msm_write(port, MSM_UART_CR_TX_ENABLE | MSM_UART_CR_RX_ENABLE, MSM_UART_CR);
1170 /* turn on RX and CTS interrupts */
1171 msm_port->imr = MSM_UART_IMR_RXLEV | MSM_UART_IMR_RXSTALE |
1172 MSM_UART_IMR_CURRENT_CTS | MSM_UART_IMR_RXBREAK_START;
1174 msm_write(port, msm_port->imr, MSM_UART_IMR);
1176 if (msm_port->is_uartdm) {
1177 msm_write(port, MSM_UART_CR_CMD_RESET_STALE_INT, MSM_UART_CR);
1178 msm_write(port, 0xFFFFFF, UARTDM_DMRX);
1179 msm_write(port, MSM_UART_CR_CMD_STALE_EVENT_ENABLE, MSM_UART_CR);
1185 static void msm_init_clock(struct uart_port *port)
1187 struct msm_port *msm_port = to_msm_port(port);
1189 clk_prepare_enable(msm_port->clk);
1190 clk_prepare_enable(msm_port->pclk);
1191 msm_serial_set_mnd_regs(port);
1194 static int msm_startup(struct uart_port *port)
1196 struct msm_port *msm_port = to_msm_port(port);
1197 unsigned int data, rfr_level, mask;
1200 snprintf(msm_port->name, sizeof(msm_port->name),
1201 "msm_serial%d", port->line);
1203 msm_init_clock(port);
1205 if (likely(port->fifosize > 12))
1206 rfr_level = port->fifosize - 12;
1208 rfr_level = port->fifosize;
1210 /* set automatic RFR level */
1211 data = msm_read(port, MSM_UART_MR1);
1213 if (msm_port->is_uartdm)
1214 mask = MSM_UART_DM_MR1_AUTO_RFR_LEVEL1;
1216 mask = MSM_UART_MR1_AUTO_RFR_LEVEL1;
1219 data &= ~MSM_UART_MR1_AUTO_RFR_LEVEL0;
1220 data |= mask & (rfr_level << 2);
1221 data |= MSM_UART_MR1_AUTO_RFR_LEVEL0 & rfr_level;
1222 msm_write(port, data, MSM_UART_MR1);
1224 if (msm_port->is_uartdm) {
1225 msm_request_tx_dma(msm_port, msm_port->uart.mapbase);
1226 msm_request_rx_dma(msm_port, msm_port->uart.mapbase);
1229 ret = request_irq(port->irq, msm_uart_irq, IRQF_TRIGGER_HIGH,
1230 msm_port->name, port);
1237 if (msm_port->is_uartdm)
1238 msm_release_dma(msm_port);
1240 clk_disable_unprepare(msm_port->pclk);
1241 clk_disable_unprepare(msm_port->clk);
1246 static void msm_shutdown(struct uart_port *port)
1248 struct msm_port *msm_port = to_msm_port(port);
1251 msm_write(port, 0, MSM_UART_IMR); /* disable interrupts */
1253 if (msm_port->is_uartdm)
1254 msm_release_dma(msm_port);
1256 clk_disable_unprepare(msm_port->clk);
1258 free_irq(port->irq, port);
1261 static void msm_set_termios(struct uart_port *port, struct ktermios *termios,
1262 const struct ktermios *old)
1264 struct msm_port *msm_port = to_msm_port(port);
1265 struct msm_dma *dma = &msm_port->rx_dma;
1266 unsigned long flags;
1267 unsigned int baud, mr;
1269 uart_port_lock_irqsave(port, &flags);
1271 if (dma->chan) /* Terminate if any */
1272 msm_stop_dma(port, dma);
1274 /* calculate and set baud rate */
1275 baud = uart_get_baud_rate(port, termios, old, 300, 4000000);
1276 baud = msm_set_baud_rate(port, baud, &flags);
1277 if (tty_termios_baud_rate(termios))
1278 tty_termios_encode_baud_rate(termios, baud, baud);
1280 /* calculate parity */
1281 mr = msm_read(port, MSM_UART_MR2);
1282 mr &= ~MSM_UART_MR2_PARITY_MODE;
1283 if (termios->c_cflag & PARENB) {
1284 if (termios->c_cflag & PARODD)
1285 mr |= MSM_UART_MR2_PARITY_MODE_ODD;
1286 else if (termios->c_cflag & CMSPAR)
1287 mr |= MSM_UART_MR2_PARITY_MODE_SPACE;
1289 mr |= MSM_UART_MR2_PARITY_MODE_EVEN;
1292 /* calculate bits per char */
1293 mr &= ~MSM_UART_MR2_BITS_PER_CHAR;
1294 switch (termios->c_cflag & CSIZE) {
1296 mr |= MSM_UART_MR2_BITS_PER_CHAR_5;
1299 mr |= MSM_UART_MR2_BITS_PER_CHAR_6;
1302 mr |= MSM_UART_MR2_BITS_PER_CHAR_7;
1306 mr |= MSM_UART_MR2_BITS_PER_CHAR_8;
1310 /* calculate stop bits */
1311 mr &= ~(MSM_UART_MR2_STOP_BIT_LEN_ONE | MSM_UART_MR2_STOP_BIT_LEN_TWO);
1312 if (termios->c_cflag & CSTOPB)
1313 mr |= MSM_UART_MR2_STOP_BIT_LEN_TWO;
1315 mr |= MSM_UART_MR2_STOP_BIT_LEN_ONE;
1317 /* set parity, bits per char, and stop bit */
1318 msm_write(port, mr, MSM_UART_MR2);
1320 /* calculate and set hardware flow control */
1321 mr = msm_read(port, MSM_UART_MR1);
1322 mr &= ~(MSM_UART_MR1_CTS_CTL | MSM_UART_MR1_RX_RDY_CTL);
1323 if (termios->c_cflag & CRTSCTS) {
1324 mr |= MSM_UART_MR1_CTS_CTL;
1325 mr |= MSM_UART_MR1_RX_RDY_CTL;
1327 msm_write(port, mr, MSM_UART_MR1);
1329 /* Configure status bits to ignore based on termio flags. */
1330 port->read_status_mask = 0;
1331 if (termios->c_iflag & INPCK)
1332 port->read_status_mask |= MSM_UART_SR_PAR_FRAME_ERR;
1333 if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
1334 port->read_status_mask |= MSM_UART_SR_RX_BREAK;
1336 uart_update_timeout(port, termios->c_cflag, baud);
1338 /* Try to use DMA */
1339 msm_start_rx_dma(msm_port);
1341 uart_port_unlock_irqrestore(port, flags);
1344 static const char *msm_type(struct uart_port *port)
1349 static void msm_release_port(struct uart_port *port)
1351 struct platform_device *pdev = to_platform_device(port->dev);
1352 struct resource *uart_resource;
1353 resource_size_t size;
1355 uart_resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1356 if (unlikely(!uart_resource))
1358 size = resource_size(uart_resource);
1360 release_mem_region(port->mapbase, size);
1361 iounmap(port->membase);
1362 port->membase = NULL;
1365 static int msm_request_port(struct uart_port *port)
1367 struct platform_device *pdev = to_platform_device(port->dev);
1368 struct resource *uart_resource;
1369 resource_size_t size;
1372 uart_resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1373 if (unlikely(!uart_resource))
1376 size = resource_size(uart_resource);
1378 if (!request_mem_region(port->mapbase, size, "msm_serial"))
1381 port->membase = ioremap(port->mapbase, size);
1382 if (!port->membase) {
1384 goto fail_release_port;
1390 release_mem_region(port->mapbase, size);
1394 static void msm_config_port(struct uart_port *port, int flags)
1398 if (flags & UART_CONFIG_TYPE) {
1399 port->type = PORT_MSM;
1400 ret = msm_request_port(port);
1406 static int msm_verify_port(struct uart_port *port, struct serial_struct *ser)
1408 if (unlikely(ser->type != PORT_UNKNOWN && ser->type != PORT_MSM))
1410 if (unlikely(port->irq != ser->irq))
1415 static void msm_power(struct uart_port *port, unsigned int state,
1416 unsigned int oldstate)
1418 struct msm_port *msm_port = to_msm_port(port);
1422 clk_prepare_enable(msm_port->clk);
1423 clk_prepare_enable(msm_port->pclk);
1426 clk_disable_unprepare(msm_port->clk);
1427 clk_disable_unprepare(msm_port->pclk);
1430 pr_err("msm_serial: Unknown PM state %d\n", state);
1434 #ifdef CONFIG_CONSOLE_POLL
1435 static int msm_poll_get_char_single(struct uart_port *port)
1437 struct msm_port *msm_port = to_msm_port(port);
1438 unsigned int rf_reg = msm_port->is_uartdm ? UARTDM_RF : MSM_UART_RF;
1440 if (!(msm_read(port, MSM_UART_SR) & MSM_UART_SR_RX_READY))
1441 return NO_POLL_CHAR;
1443 return msm_read(port, rf_reg) & 0xff;
1446 static int msm_poll_get_char_dm(struct uart_port *port)
1451 unsigned char *sp = (unsigned char *)&slop;
1453 /* Check if a previous read had more than one char */
1455 c = sp[sizeof(slop) - count];
1457 /* Or if FIFO is empty */
1458 } else if (!(msm_read(port, MSM_UART_SR) & MSM_UART_SR_RX_READY)) {
1460 * If RX packing buffer has less than a word, force stale to
1461 * push contents into RX FIFO
1463 count = msm_read(port, UARTDM_RXFS);
1464 count = (count >> UARTDM_RXFS_BUF_SHIFT) & UARTDM_RXFS_BUF_MASK;
1466 msm_write(port, MSM_UART_CR_CMD_FORCE_STALE, MSM_UART_CR);
1467 slop = msm_read(port, UARTDM_RF);
1470 msm_write(port, MSM_UART_CR_CMD_RESET_STALE_INT, MSM_UART_CR);
1471 msm_write(port, 0xFFFFFF, UARTDM_DMRX);
1472 msm_write(port, MSM_UART_CR_CMD_STALE_EVENT_ENABLE, MSM_UART_CR);
1476 /* FIFO has a word */
1478 slop = msm_read(port, UARTDM_RF);
1480 count = sizeof(slop) - 1;
1486 static int msm_poll_get_char(struct uart_port *port)
1490 struct msm_port *msm_port = to_msm_port(port);
1492 /* Disable all interrupts */
1493 imr = msm_read(port, MSM_UART_IMR);
1494 msm_write(port, 0, MSM_UART_IMR);
1496 if (msm_port->is_uartdm)
1497 c = msm_poll_get_char_dm(port);
1499 c = msm_poll_get_char_single(port);
1501 /* Enable interrupts */
1502 msm_write(port, imr, MSM_UART_IMR);
1507 static void msm_poll_put_char(struct uart_port *port, unsigned char c)
1510 struct msm_port *msm_port = to_msm_port(port);
1512 /* Disable all interrupts */
1513 imr = msm_read(port, MSM_UART_IMR);
1514 msm_write(port, 0, MSM_UART_IMR);
1516 if (msm_port->is_uartdm)
1517 msm_reset_dm_count(port, 1);
1519 /* Wait until FIFO is empty */
1520 while (!(msm_read(port, MSM_UART_SR) & MSM_UART_SR_TX_READY))
1523 /* Write a character */
1524 msm_write(port, c, msm_port->is_uartdm ? UARTDM_TF : MSM_UART_TF);
1526 /* Wait until FIFO is empty */
1527 while (!(msm_read(port, MSM_UART_SR) & MSM_UART_SR_TX_READY))
1530 /* Enable interrupts */
1531 msm_write(port, imr, MSM_UART_IMR);
1535 static const struct uart_ops msm_uart_pops = {
1536 .tx_empty = msm_tx_empty,
1537 .set_mctrl = msm_set_mctrl,
1538 .get_mctrl = msm_get_mctrl,
1539 .stop_tx = msm_stop_tx,
1540 .start_tx = msm_start_tx,
1541 .stop_rx = msm_stop_rx,
1542 .enable_ms = msm_enable_ms,
1543 .break_ctl = msm_break_ctl,
1544 .startup = msm_startup,
1545 .shutdown = msm_shutdown,
1546 .set_termios = msm_set_termios,
1548 .release_port = msm_release_port,
1549 .request_port = msm_request_port,
1550 .config_port = msm_config_port,
1551 .verify_port = msm_verify_port,
1553 #ifdef CONFIG_CONSOLE_POLL
1554 .poll_get_char = msm_poll_get_char,
1555 .poll_put_char = msm_poll_put_char,
1559 static struct msm_port msm_uart_ports[] = {
1563 .ops = &msm_uart_pops,
1564 .flags = UPF_BOOT_AUTOCONF,
1572 .ops = &msm_uart_pops,
1573 .flags = UPF_BOOT_AUTOCONF,
1581 .ops = &msm_uart_pops,
1582 .flags = UPF_BOOT_AUTOCONF,
1589 #define MSM_UART_NR ARRAY_SIZE(msm_uart_ports)
1591 static inline struct uart_port *msm_get_port_from_line(unsigned int line)
1593 return &msm_uart_ports[line].uart;
1596 #ifdef CONFIG_SERIAL_MSM_CONSOLE
1597 static void __msm_console_write(struct uart_port *port, const char *s,
1598 unsigned int count, bool is_uartdm)
1600 unsigned long flags;
1602 int num_newlines = 0;
1603 bool replaced = false;
1608 tf = port->membase + UARTDM_TF;
1610 tf = port->membase + MSM_UART_TF;
1612 /* Account for newlines that will get a carriage return added */
1613 for (i = 0; i < count; i++)
1616 count += num_newlines;
1618 local_irq_save(flags);
1622 else if (oops_in_progress)
1623 locked = uart_port_trylock(port);
1625 uart_port_lock(port);
1628 msm_reset_dm_count(port, count);
1633 unsigned int num_chars;
1634 char buf[4] = { 0 };
1637 num_chars = min(count - i, (unsigned int)sizeof(buf));
1641 for (j = 0; j < num_chars; j++) {
1644 if (c == '\n' && !replaced) {
1649 if (j < num_chars) {
1656 while (!(msm_read(port, MSM_UART_SR) & MSM_UART_SR_TX_READY))
1659 iowrite32_rep(tf, buf, 1);
1664 uart_port_unlock(port);
1666 local_irq_restore(flags);
1669 static void msm_console_write(struct console *co, const char *s,
1672 struct uart_port *port;
1673 struct msm_port *msm_port;
1675 BUG_ON(co->index < 0 || co->index >= MSM_UART_NR);
1677 port = msm_get_port_from_line(co->index);
1678 msm_port = to_msm_port(port);
1680 __msm_console_write(port, s, count, msm_port->is_uartdm);
1683 static int msm_console_setup(struct console *co, char *options)
1685 struct uart_port *port;
1691 if (unlikely(co->index >= MSM_UART_NR || co->index < 0))
1694 port = msm_get_port_from_line(co->index);
1696 if (unlikely(!port->membase))
1699 msm_init_clock(port);
1702 uart_parse_options(options, &baud, &parity, &bits, &flow);
1704 pr_info("msm_serial: console setup on port #%d\n", port->line);
1706 return uart_set_options(port, co, baud, parity, bits, flow);
1710 msm_serial_early_write(struct console *con, const char *s, unsigned n)
1712 struct earlycon_device *dev = con->data;
1714 __msm_console_write(&dev->port, s, n, false);
1718 msm_serial_early_console_setup(struct earlycon_device *device, const char *opt)
1720 if (!device->port.membase)
1723 device->con->write = msm_serial_early_write;
1726 OF_EARLYCON_DECLARE(msm_serial, "qcom,msm-uart",
1727 msm_serial_early_console_setup);
1730 msm_serial_early_write_dm(struct console *con, const char *s, unsigned n)
1732 struct earlycon_device *dev = con->data;
1734 __msm_console_write(&dev->port, s, n, true);
1738 msm_serial_early_console_setup_dm(struct earlycon_device *device,
1741 if (!device->port.membase)
1744 device->con->write = msm_serial_early_write_dm;
1747 OF_EARLYCON_DECLARE(msm_serial_dm, "qcom,msm-uartdm",
1748 msm_serial_early_console_setup_dm);
1750 static struct uart_driver msm_uart_driver;
1752 static struct console msm_console = {
1754 .write = msm_console_write,
1755 .device = uart_console_device,
1756 .setup = msm_console_setup,
1757 .flags = CON_PRINTBUFFER,
1759 .data = &msm_uart_driver,
1762 #define MSM_CONSOLE (&msm_console)
1765 #define MSM_CONSOLE NULL
1768 static struct uart_driver msm_uart_driver = {
1769 .owner = THIS_MODULE,
1770 .driver_name = "msm_serial",
1771 .dev_name = "ttyMSM",
1773 .cons = MSM_CONSOLE,
1776 static atomic_t msm_uart_next_id = ATOMIC_INIT(0);
1778 static const struct of_device_id msm_uartdm_table[] = {
1779 { .compatible = "qcom,msm-uartdm-v1.1", .data = (void *)UARTDM_1P1 },
1780 { .compatible = "qcom,msm-uartdm-v1.2", .data = (void *)UARTDM_1P2 },
1781 { .compatible = "qcom,msm-uartdm-v1.3", .data = (void *)UARTDM_1P3 },
1782 { .compatible = "qcom,msm-uartdm-v1.4", .data = (void *)UARTDM_1P4 },
1786 static int msm_serial_probe(struct platform_device *pdev)
1788 struct msm_port *msm_port;
1789 struct resource *resource;
1790 struct uart_port *port;
1791 const struct of_device_id *id;
1794 if (pdev->dev.of_node)
1795 line = of_alias_get_id(pdev->dev.of_node, "serial");
1800 line = atomic_inc_return(&msm_uart_next_id) - 1;
1802 if (unlikely(line < 0 || line >= MSM_UART_NR))
1805 dev_info(&pdev->dev, "msm_serial: detected port #%d\n", line);
1807 port = msm_get_port_from_line(line);
1808 port->dev = &pdev->dev;
1809 msm_port = to_msm_port(port);
1811 id = of_match_device(msm_uartdm_table, &pdev->dev);
1813 msm_port->is_uartdm = (unsigned long)id->data;
1815 msm_port->is_uartdm = 0;
1817 msm_port->clk = devm_clk_get(&pdev->dev, "core");
1818 if (IS_ERR(msm_port->clk))
1819 return PTR_ERR(msm_port->clk);
1821 if (msm_port->is_uartdm) {
1822 msm_port->pclk = devm_clk_get(&pdev->dev, "iface");
1823 if (IS_ERR(msm_port->pclk))
1824 return PTR_ERR(msm_port->pclk);
1827 port->uartclk = clk_get_rate(msm_port->clk);
1828 dev_info(&pdev->dev, "uartclk = %d\n", port->uartclk);
1830 resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1831 if (unlikely(!resource))
1833 port->mapbase = resource->start;
1835 irq = platform_get_irq(pdev, 0);
1836 if (unlikely(irq < 0))
1839 port->has_sysrq = IS_ENABLED(CONFIG_SERIAL_MSM_CONSOLE);
1841 platform_set_drvdata(pdev, port);
1843 return uart_add_one_port(&msm_uart_driver, port);
1846 static int msm_serial_remove(struct platform_device *pdev)
1848 struct uart_port *port = platform_get_drvdata(pdev);
1850 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 = 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);
1921 MODULE_DESCRIPTION("Driver for msm7x serial device");
1922 MODULE_LICENSE("GPL");