diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2023-07-03 13:14:58 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2023-07-03 13:14:58 -0700 |
commit | 868a9fd9480785952336e5f119e1f75877c423a8 (patch) | |
tree | 87b6985e624d976da7524b90907bda8262cdc43c /drivers/tty/serial/fsl_lpuart.c | |
parent | db9c6d1d7fcc6dc803f042bf3d29bbff91837f57 (diff) | |
parent | e534755c9412be07f579acd2947401a9f87a33c8 (diff) |
Merge tag 'tty-6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial driver updates from Greg KH:
"Here is the big set of tty/serial driver updates for 6.5-rc1.
Included in here are:
- tty_audit code cleanups from Jiri
- more 8250 cleanups from Ilpo
- samsung_tty driver bugfixes
- 8250 lock port updates
- usual fsl_lpuart driver updates and fixes
- other small serial driver fixes and updates, full details in the
shortlog
All of these have been in linux-next for a while with no reported
issues"
* tag 'tty-6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (58 commits)
tty_audit: make data of tty_audit_log() const
tty_audit: make tty pointers in exposed functions const
tty_audit: make icanon a bool
tty_audit: invert the condition in tty_audit_log()
tty_audit: use kzalloc() in tty_audit_buf_alloc()
tty_audit: use TASK_COMM_LEN for task comm
Revert "8250: add support for ASIX devices with a FIFO bug"
serial: atmel: don't enable IRQs prematurely
tty: serial: Add Nuvoton ma35d1 serial driver support
tty: serial: fsl_lpuart: add earlycon for imx8ulp platform
tty: serial: imx: fix rs485 rx after tx
selftests: tty: add selftest for tty timestamp updates
tty: tty_io: update timestamps on all device nodes
tty: fix hang on tty device with no_room set
serial: core: fix -EPROBE_DEFER handling in init
serial: 8250_omap: Use force_suspend and resume for system suspend
tty: serial: samsung_tty: Use abs() to simplify some code
tty: serial: samsung_tty: Fix a memory leak in s3c24xx_serial_getclk() when iterating clk
tty: serial: samsung_tty: Fix a memory leak in s3c24xx_serial_getclk() in case of error
serial: 8250: Apply FSL workarounds also without SERIAL_8250_CONSOLE
...
Diffstat (limited to 'drivers/tty/serial/fsl_lpuart.c')
-rw-r--r-- | drivers/tty/serial/fsl_lpuart.c | 57 |
1 files changed, 53 insertions, 4 deletions
diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c index 7fd30fcc10c6..4d80fae20177 100644 --- a/drivers/tty/serial/fsl_lpuart.c +++ b/drivers/tty/serial/fsl_lpuart.c @@ -238,6 +238,7 @@ /* Rx DMA timeout in ms, which is used to calculate Rx ring buffer size */ #define DMA_RX_TIMEOUT (10) +#define DMA_RX_IDLE_CHARS 8 #define UART_AUTOSUSPEND_TIMEOUT 3000 #define DRIVER_NAME "fsl-lpuart" @@ -282,6 +283,7 @@ struct lpuart_port { struct scatterlist rx_sgl, tx_sgl[2]; struct circ_buf rx_ring; int rx_dma_rng_buf_len; + int last_residue; unsigned int dma_tx_nents; wait_queue_head_t dma_wait; bool is_cs7; /* Set to true when character size is 7 */ @@ -331,7 +333,7 @@ static struct lpuart_soc_data imx8qxp_data = { .devtype = IMX8QXP_LPUART, .iotype = UPIO_MEM32, .reg_off = IMX_REG_OFF, - .rx_watermark = 31, + .rx_watermark = 7, /* A lower watermark is ideal for low baud rates. */ }; static struct lpuart_soc_data imxrt1050_data = { .devtype = IMXRT1050_LPUART, @@ -1255,6 +1257,8 @@ static void lpuart_copy_rx_to_tty(struct lpuart_port *sport) sport->port.icount.rx += copied; } + sport->last_residue = state.residue; + exit: dma_sync_sg_for_device(chan->device->dev, &sport->rx_sgl, 1, DMA_FROM_DEVICE); @@ -1272,11 +1276,43 @@ static void lpuart_dma_rx_complete(void *arg) lpuart_copy_rx_to_tty(sport); } +/* + * Timer function to simulate the hardware EOP (End Of Package) event. + * The timer callback is to check for new RX data and copy to TTY buffer. + * If no new data are received since last interval, the EOP condition is + * met, complete the DMA transfer by copying the data. Otherwise, just + * restart timer. + */ static void lpuart_timer_func(struct timer_list *t) { struct lpuart_port *sport = from_timer(sport, t, lpuart_timer); + enum dma_status dmastat; + struct dma_chan *chan = sport->dma_rx_chan; + struct circ_buf *ring = &sport->rx_ring; + struct dma_tx_state state; + unsigned long flags; + int count; - lpuart_copy_rx_to_tty(sport); + dmastat = dmaengine_tx_status(chan, sport->dma_rx_cookie, &state); + if (dmastat == DMA_ERROR) { + dev_err(sport->port.dev, "Rx DMA transfer failed!\n"); + return; + } + + ring->head = sport->rx_sgl.length - state.residue; + count = CIRC_CNT(ring->head, ring->tail, sport->rx_sgl.length); + + /* Check if new data received before copying */ + if ((count != 0) && (sport->last_residue == state.residue)) + lpuart_copy_rx_to_tty(sport); + else + mod_timer(&sport->lpuart_timer, + jiffies + sport->dma_rx_timeout); + + if (spin_trylock_irqsave(&sport->port.lock, flags)) { + sport->last_residue = state.residue; + spin_unlock_irqrestore(&sport->port.lock, flags); + } } static inline int lpuart_start_rx_dma(struct lpuart_port *sport) @@ -1297,9 +1333,20 @@ static inline int lpuart_start_rx_dma(struct lpuart_port *sport) */ 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)); + sport->rx_dma_rng_buf_len = max_t(int, + sport->rxfifo_size * 2, + sport->rx_dma_rng_buf_len); + /* + * Keep this condition check in case rxfifo_size is unavailable + * for some SoCs. + */ if (sport->rx_dma_rng_buf_len < 16) sport->rx_dma_rng_buf_len = 16; + sport->last_residue = 0; + sport->dma_rx_timeout = max(nsecs_to_jiffies( + sport->port.frame_time * DMA_RX_IDLE_CHARS), 1UL); + ring->buf = kzalloc(sport->rx_dma_rng_buf_len, GFP_ATOMIC); if (!ring->buf) return -ENOMEM; @@ -1689,12 +1736,13 @@ static void lpuart_rx_dma_startup(struct lpuart_port *sport) if (!sport->dma_rx_chan) goto err; + /* set default Rx DMA timeout */ + sport->dma_rx_timeout = msecs_to_jiffies(DMA_RX_TIMEOUT); + 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; @@ -2676,6 +2724,7 @@ 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); |