Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753743Ab2HUJWP (ORCPT ); Tue, 21 Aug 2012 05:22:15 -0400 Received: from na3sys009aog113.obsmtp.com ([74.125.149.209]:57054 "EHLO na3sys009aog113.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755402Ab2HUJUX (ORCPT ); Tue, 21 Aug 2012 05:20:23 -0400 From: Felipe Balbi To: alan@linux.intel.com Cc: Tony Lindgren , Kevin Hilman , Linux OMAP Mailing List , Linux ARM Kernel Mailing List , linux-serial@vger.kernel.org, Linux Kernel Mailing List , Santosh Shilimkar , Shubhrajyoti Datta , Felipe Balbi Subject: [RFC/PATCH 05/13] serial: omap: drop DMA support Date: Tue, 21 Aug 2012 12:15:47 +0300 Message-Id: <1345540555-24359-6-git-send-email-balbi@ti.com> X-Mailer: git-send-email 1.7.12.rc3 In-Reply-To: <1345540555-24359-1-git-send-email-balbi@ti.com> References: <1345540555-24359-1-git-send-email-balbi@ti.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 15819 Lines: 484 The current support is known to be broken and a later patch will come re-adding it using dma engine API. Signed-off-by: Felipe Balbi --- drivers/tty/serial/omap-serial.c | 330 ++------------------------------------- 1 file changed, 12 insertions(+), 318 deletions(-) diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c index fb81366..4d74a9b 100644 --- a/drivers/tty/serial/omap-serial.c +++ b/drivers/tty/serial/omap-serial.c @@ -33,14 +33,12 @@ #include #include #include -#include #include #include #include #include #include -#include #include #include @@ -74,9 +72,6 @@ static struct uart_omap_port *ui[OMAP_MAX_HSUART_PORTS]; /* Forward declaration of functions */ -static void uart_tx_dma_callback(int lch, u16 ch_status, void *data); -static void serial_omap_rxdma_poll(unsigned long uart_no); -static int serial_omap_start_rxdma(struct uart_omap_port *up); static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1); static struct workqueue_struct *serial_omap_uart_wq; @@ -160,19 +155,6 @@ serial_omap_get_divisor(struct uart_port *port, unsigned int baud) return port->uartclk/(baud * divisor); } -static void serial_omap_stop_rxdma(struct uart_omap_port *up) -{ - if (up->uart_dma.rx_dma_used) { - del_timer(&up->uart_dma.rx_timer); - omap_stop_dma(up->uart_dma.rx_dma_channel); - omap_free_dma(up->uart_dma.rx_dma_channel); - up->uart_dma.rx_dma_channel = OMAP_UART_DMA_CH_FREE; - up->uart_dma.rx_dma_used = false; - pm_runtime_mark_last_busy(up->dev); - pm_runtime_put_autosuspend(up->dev); - } -} - static void serial_omap_enable_ms(struct uart_port *port) { struct uart_omap_port *up = to_uart_omap_port(port); @@ -188,22 +170,6 @@ static void serial_omap_enable_ms(struct uart_port *port) static void serial_omap_stop_tx(struct uart_port *port) { struct uart_omap_port *up = to_uart_omap_port(port); - struct omap_uart_port_info *pdata = up->dev->platform_data; - - if (up->use_dma && - up->uart_dma.tx_dma_channel != OMAP_UART_DMA_CH_FREE) { - /* - * Check if dma is still active. If yes do nothing, - * return. Else stop dma - */ - if (omap_get_dma_active_status(up->uart_dma.tx_dma_channel)) - return; - omap_stop_dma(up->uart_dma.tx_dma_channel); - omap_free_dma(up->uart_dma.tx_dma_channel); - up->uart_dma.tx_dma_channel = OMAP_UART_DMA_CH_FREE; - pm_runtime_mark_last_busy(up->dev); - pm_runtime_put_autosuspend(up->dev); - } pm_runtime_get_sync(up->dev); if (up->ier & UART_IER_THRI) { @@ -211,8 +177,7 @@ static void serial_omap_stop_tx(struct uart_port *port) serial_out(up, UART_IER, up->ier); } - if (!up->use_dma && pdata) - serial_omap_set_forceidle(up); + serial_omap_set_forceidle(up); pm_runtime_mark_last_busy(up->dev); pm_runtime_put_autosuspend(up->dev); @@ -223,8 +188,6 @@ static void serial_omap_stop_rx(struct uart_port *port) struct uart_omap_port *up = to_uart_omap_port(port); pm_runtime_get_sync(up->dev); - if (up->use_dma) - serial_omap_stop_rxdma(up); up->ier &= ~UART_IER_RLSI; up->port.read_status_mask &= ~UART_LSR_DR; serial_out(up, UART_IER, up->ier); @@ -342,67 +305,12 @@ static inline void serial_omap_enable_ier_thri(struct uart_omap_port *up) static void serial_omap_start_tx(struct uart_port *port) { struct uart_omap_port *up = to_uart_omap_port(port); - struct circ_buf *xmit; - unsigned int start; - int ret = 0; - - if (!up->use_dma) { - pm_runtime_get_sync(up->dev); - serial_omap_enable_ier_thri(up); - serial_omap_set_noidle(up); - pm_runtime_mark_last_busy(up->dev); - pm_runtime_put_autosuspend(up->dev); - return; - } - - if (up->uart_dma.tx_dma_used) - return; - - xmit = &up->port.state->xmit; - - if (up->uart_dma.tx_dma_channel == OMAP_UART_DMA_CH_FREE) { - pm_runtime_get_sync(up->dev); - ret = omap_request_dma(up->uart_dma.uart_dma_tx, - "UART Tx DMA", - (void *)uart_tx_dma_callback, up, - &(up->uart_dma.tx_dma_channel)); - if (ret < 0) { - serial_omap_enable_ier_thri(up); - return; - } - } - spin_lock(&(up->uart_dma.tx_lock)); - up->uart_dma.tx_dma_used = true; - spin_unlock(&(up->uart_dma.tx_lock)); - - start = up->uart_dma.tx_buf_dma_phys + - (xmit->tail & (UART_XMIT_SIZE - 1)); - - up->uart_dma.tx_buf_size = uart_circ_chars_pending(xmit); - /* - * It is a circular buffer. See if the buffer has wounded back. - * If yes it will have to be transferred in two separate dma - * transfers - */ - if (start + up->uart_dma.tx_buf_size >= - up->uart_dma.tx_buf_dma_phys + UART_XMIT_SIZE) - up->uart_dma.tx_buf_size = - (up->uart_dma.tx_buf_dma_phys + - UART_XMIT_SIZE) - start; - - omap_set_dma_dest_params(up->uart_dma.tx_dma_channel, 0, - OMAP_DMA_AMODE_CONSTANT, - up->uart_dma.uart_base, 0, 0); - omap_set_dma_src_params(up->uart_dma.tx_dma_channel, 0, - OMAP_DMA_AMODE_POST_INC, start, 0, 0); - omap_set_dma_transfer_params(up->uart_dma.tx_dma_channel, - OMAP_DMA_DATA_TYPE_S8, - up->uart_dma.tx_buf_size, 1, - OMAP_DMA_SYNC_ELEMENT, - up->uart_dma.uart_dma_tx, 0); - /* FIXME: Cache maintenance needed here? */ - omap_start_dma(up->uart_dma.tx_dma_channel); + pm_runtime_get_sync(up->dev); + serial_omap_enable_ier_thri(up); + serial_omap_set_noidle(up); + pm_runtime_mark_last_busy(up->dev); + pm_runtime_put_autosuspend(up->dev); } static unsigned int check_modem_status(struct uart_omap_port *up) @@ -455,16 +363,8 @@ static inline irqreturn_t serial_omap_irq(int irq, void *dev_id) spin_lock_irqsave(&up->port.lock, flags); lsr = serial_in(up, UART_LSR); if (iir & UART_IIR_RLSI) { - if (!up->use_dma) { - if (lsr & UART_LSR_DR) - receive_chars(up, &lsr); - } else { - up->ier &= ~(UART_IER_RDI | UART_IER_RLSI); - serial_out(up, UART_IER, up->ier); - if ((serial_omap_start_rxdma(up) != 0) && - (lsr & UART_LSR_DR)) - receive_chars(up, &lsr); - } + if (lsr & UART_LSR_DR) + receive_chars(up, &lsr); } check_modem_status(up); @@ -605,20 +505,6 @@ static int serial_omap_startup(struct uart_port *port) spin_unlock_irqrestore(&up->port.lock, flags); up->msr_saved_flags = 0; - if (up->use_dma) { - free_page((unsigned long)up->port.state->xmit.buf); - up->port.state->xmit.buf = dma_alloc_coherent(NULL, - UART_XMIT_SIZE, - (dma_addr_t *)&(up->uart_dma.tx_buf_dma_phys), - 0); - init_timer(&(up->uart_dma.rx_timer)); - up->uart_dma.rx_timer.function = serial_omap_rxdma_poll; - up->uart_dma.rx_timer.data = up->port.line; - /* Currently the buffer size is 4KB. Can increase it */ - up->uart_dma.rx_buf = dma_alloc_coherent(NULL, - up->uart_dma.rx_buf_size, - (dma_addr_t *)&(up->uart_dma.rx_buf_dma_phys), 0); - } /* * Finally, enable interrupts. Note: Modem status interrupts * are set via set_termios(), which will be occurring imminently @@ -666,17 +552,6 @@ static void serial_omap_shutdown(struct uart_port *port) */ if (serial_in(up, UART_LSR) & UART_LSR_DR) (void) serial_in(up, UART_RX); - if (up->use_dma) { - dma_free_coherent(up->port.dev, - UART_XMIT_SIZE, up->port.state->xmit.buf, - up->uart_dma.tx_buf_dma_phys); - up->port.state->xmit.buf = NULL; - serial_omap_stop_rx(port); - dma_free_coherent(up->port.dev, - up->uart_dma.rx_buf_size, up->uart_dma.rx_buf, - up->uart_dma.rx_buf_dma_phys); - up->uart_dma.rx_buf = NULL; - } pm_runtime_put(up->dev); free_irq(up->port.irq, up); @@ -800,8 +675,6 @@ serial_omap_set_termios(struct uart_port *port, struct ktermios *termios, up->fcr = UART_FCR_R_TRIG_01 | UART_FCR_T_TRIG_01 | UART_FCR_ENABLE_FIFO; - if (up->use_dma) - up->fcr |= UART_FCR_DMA_SELECT; /* * Ok, we're now changing the port state. Do it with @@ -877,14 +750,9 @@ serial_omap_set_termios(struct uart_port *port, struct ktermios *termios, up->scr |= OMAP_UART_SCR_RX_TRIG_GRANU1_MASK; - if (up->use_dma) { - serial_out(up, UART_TI752_TLR, 0); - up->scr |= UART_FCR_TRIGGER_4; - } else { - /* Set receive FIFO threshold to 1 byte */ - up->fcr &= ~OMAP_UART_FCR_RX_FIFO_TRIG_MASK; - up->fcr |= (0x1 << OMAP_UART_FCR_RX_FIFO_TRIG_SHIFT); - } + /* Set receive FIFO threshold to 1 byte */ + up->fcr &= ~OMAP_UART_FCR_RX_FIFO_TRIG_MASK; + up->fcr |= (0x1 << OMAP_UART_FCR_RX_FIFO_TRIG_SHIFT); serial_out(up, UART_FCR, up->fcr); serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); @@ -1253,149 +1121,6 @@ static int serial_omap_resume(struct device *dev) } #endif -static void serial_omap_rxdma_poll(unsigned long uart_no) -{ - struct uart_omap_port *up = ui[uart_no]; - unsigned int curr_dma_pos, curr_transmitted_size; - int ret = 0; - - curr_dma_pos = omap_get_dma_dst_pos(up->uart_dma.rx_dma_channel); - if ((curr_dma_pos == up->uart_dma.prev_rx_dma_pos) || - (curr_dma_pos == 0)) { - if (jiffies_to_msecs(jiffies - up->port_activity) < - up->uart_dma.rx_timeout) { - mod_timer(&up->uart_dma.rx_timer, jiffies + - usecs_to_jiffies(up->uart_dma.rx_poll_rate)); - } else { - serial_omap_stop_rxdma(up); - up->ier |= (UART_IER_RDI | UART_IER_RLSI); - serial_out(up, UART_IER, up->ier); - } - return; - } - - curr_transmitted_size = curr_dma_pos - - up->uart_dma.prev_rx_dma_pos; - up->port.icount.rx += curr_transmitted_size; - tty_insert_flip_string(up->port.state->port.tty, - up->uart_dma.rx_buf + - (up->uart_dma.prev_rx_dma_pos - - up->uart_dma.rx_buf_dma_phys), - curr_transmitted_size); - tty_flip_buffer_push(up->port.state->port.tty); - up->uart_dma.prev_rx_dma_pos = curr_dma_pos; - if (up->uart_dma.rx_buf_size + - up->uart_dma.rx_buf_dma_phys == curr_dma_pos) { - ret = serial_omap_start_rxdma(up); - if (ret < 0) { - serial_omap_stop_rxdma(up); - up->ier |= (UART_IER_RDI | UART_IER_RLSI); - serial_out(up, UART_IER, up->ier); - } - } else { - mod_timer(&up->uart_dma.rx_timer, jiffies + - usecs_to_jiffies(up->uart_dma.rx_poll_rate)); - } - up->port_activity = jiffies; -} - -static void uart_rx_dma_callback(int lch, u16 ch_status, void *data) -{ - return; -} - -static int serial_omap_start_rxdma(struct uart_omap_port *up) -{ - int ret = 0; - - if (up->uart_dma.rx_dma_channel == -1) { - pm_runtime_get_sync(up->dev); - ret = omap_request_dma(up->uart_dma.uart_dma_rx, - "UART Rx DMA", - (void *)uart_rx_dma_callback, up, - &(up->uart_dma.rx_dma_channel)); - if (ret < 0) - return ret; - - omap_set_dma_src_params(up->uart_dma.rx_dma_channel, 0, - OMAP_DMA_AMODE_CONSTANT, - up->uart_dma.uart_base, 0, 0); - omap_set_dma_dest_params(up->uart_dma.rx_dma_channel, 0, - OMAP_DMA_AMODE_POST_INC, - up->uart_dma.rx_buf_dma_phys, 0, 0); - omap_set_dma_transfer_params(up->uart_dma.rx_dma_channel, - OMAP_DMA_DATA_TYPE_S8, - up->uart_dma.rx_buf_size, 1, - OMAP_DMA_SYNC_ELEMENT, - up->uart_dma.uart_dma_rx, 0); - } - up->uart_dma.prev_rx_dma_pos = up->uart_dma.rx_buf_dma_phys; - /* FIXME: Cache maintenance needed here? */ - omap_start_dma(up->uart_dma.rx_dma_channel); - mod_timer(&up->uart_dma.rx_timer, jiffies + - usecs_to_jiffies(up->uart_dma.rx_poll_rate)); - up->uart_dma.rx_dma_used = true; - return ret; -} - -static void serial_omap_continue_tx(struct uart_omap_port *up) -{ - struct circ_buf *xmit = &up->port.state->xmit; - unsigned int start = up->uart_dma.tx_buf_dma_phys - + (xmit->tail & (UART_XMIT_SIZE - 1)); - - if (uart_circ_empty(xmit)) - return; - - up->uart_dma.tx_buf_size = uart_circ_chars_pending(xmit); - /* - * It is a circular buffer. See if the buffer has wounded back. - * If yes it will have to be transferred in two separate dma - * transfers - */ - if (start + up->uart_dma.tx_buf_size >= - up->uart_dma.tx_buf_dma_phys + UART_XMIT_SIZE) - up->uart_dma.tx_buf_size = - (up->uart_dma.tx_buf_dma_phys + UART_XMIT_SIZE) - start; - omap_set_dma_dest_params(up->uart_dma.tx_dma_channel, 0, - OMAP_DMA_AMODE_CONSTANT, - up->uart_dma.uart_base, 0, 0); - omap_set_dma_src_params(up->uart_dma.tx_dma_channel, 0, - OMAP_DMA_AMODE_POST_INC, start, 0, 0); - omap_set_dma_transfer_params(up->uart_dma.tx_dma_channel, - OMAP_DMA_DATA_TYPE_S8, - up->uart_dma.tx_buf_size, 1, - OMAP_DMA_SYNC_ELEMENT, - up->uart_dma.uart_dma_tx, 0); - /* FIXME: Cache maintenance needed here? */ - omap_start_dma(up->uart_dma.tx_dma_channel); -} - -static void uart_tx_dma_callback(int lch, u16 ch_status, void *data) -{ - struct uart_omap_port *up = data; - struct circ_buf *xmit = &up->port.state->xmit; - - xmit->tail = (xmit->tail + up->uart_dma.tx_buf_size) & \ - (UART_XMIT_SIZE - 1); - up->port.icount.tx += up->uart_dma.tx_buf_size; - - if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) - uart_write_wakeup(&up->port); - - if (uart_circ_empty(xmit)) { - spin_lock(&(up->uart_dma.tx_lock)); - serial_omap_stop_tx(&up->port); - up->uart_dma.tx_dma_used = false; - spin_unlock(&(up->uart_dma.tx_lock)); - } else { - omap_stop_dma(up->uart_dma.tx_dma_channel); - serial_omap_continue_tx(up); - } - up->port_activity = jiffies; - return; -} - static void omap_serial_fill_features_erratas(struct uart_omap_port *up) { u32 mvr, scheme; @@ -1465,7 +1190,7 @@ static struct omap_uart_port_info *of_get_uart_port_info(struct device *dev) static int serial_omap_probe(struct platform_device *pdev) { struct uart_omap_port *up; - struct resource *mem, *irq, *dma_tx, *dma_rx; + struct resource *mem, *irq; struct omap_uart_port_info *omap_up_info = pdev->dev.platform_data; int ret = -ENOSPC; @@ -1490,14 +1215,6 @@ static int serial_omap_probe(struct platform_device *pdev) return -EBUSY; } - dma_rx = platform_get_resource_byname(pdev, IORESOURCE_DMA, "rx"); - if (!dma_rx) - return -ENXIO; - - dma_tx = platform_get_resource_byname(pdev, IORESOURCE_DMA, "tx"); - if (!dma_tx) - return -ENXIO; - up = devm_kzalloc(&pdev->dev, sizeof(*up), GFP_KERNEL); if (!up) return -ENOMEM; @@ -1541,20 +1258,6 @@ static int serial_omap_probe(struct platform_device *pdev) dev_warn(&pdev->dev, "No clock speed specified: using default:" "%d\n", DEFAULT_CLK_SPEED); } - up->uart_dma.uart_base = mem->start; - - if (omap_up_info->dma_enabled) { - up->uart_dma.uart_dma_tx = dma_tx->start; - up->uart_dma.uart_dma_rx = dma_rx->start; - up->use_dma = 1; - up->uart_dma.rx_buf_size = omap_up_info->dma_rx_buf_size; - up->uart_dma.rx_timeout = omap_up_info->dma_rx_timeout; - up->uart_dma.rx_poll_rate = omap_up_info->dma_rx_poll_rate; - spin_lock_init(&(up->uart_dma.tx_lock)); - spin_lock_init(&(up->uart_dma.rx_lock)); - up->uart_dma.tx_dma_channel = OMAP_UART_DMA_CH_FREE; - up->uart_dma.rx_dma_channel = OMAP_UART_DMA_CH_FREE; - } up->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE; up->calc_latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE; @@ -1697,10 +1400,6 @@ static int serial_omap_runtime_suspend(struct device *dev) } } - /* Errata i291 */ - if (up->use_dma && (up->errata & UART_ERRATA_i291_DMA_FORCEIDLE)) - serial_omap_set_forceidle(up); - up->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE; schedule_work(&up->qos_work); @@ -1718,11 +1417,6 @@ static int serial_omap_runtime_resume(struct device *dev) if (up->context_loss_cnt != loss_cnt) serial_omap_restore_context(up); - /* Errata i291 */ - if ((up->errata & UART_ERRATA_i291_DMA_FORCEIDLE) && - up->use_dma) - serial_omap_set_noidle(up); - up->latency = up->calc_latency; schedule_work(&up->qos_work); } -- 1.7.12.rc3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/