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authorLinus Torvalds <torvalds@linux-foundation.org>2011-01-06 16:50:35 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2011-01-06 16:50:35 -0800
commit3c0cb7c31c206aaedb967e44b98442bbeb17a6c4 (patch)
tree3ecba45d7ffae4fba4a5aafaef4af5b0b1105bde /drivers/serial
parentf70f5b9dc74ca7d0a64c4ead3fb28da09dc1b234 (diff)
parent404a02cbd2ae8bf256a2fa1169bdfe86bb5ebb34 (diff)
downloadop-kernel-dev-3c0cb7c31c206aaedb967e44b98442bbeb17a6c4.zip
op-kernel-dev-3c0cb7c31c206aaedb967e44b98442bbeb17a6c4.tar.gz
Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm: (416 commits) ARM: DMA: add support for DMA debugging ARM: PL011: add DMA burst threshold support for ST variants ARM: PL011: Add support for transmit DMA ARM: PL011: Ensure IRQs are disabled in UART interrupt handler ARM: PL011: Separate hardware FIFO size from TTY FIFO size ARM: PL011: Allow better handling of vendor data ARM: PL011: Ensure error flags are clear at startup ARM: PL011: include revision number in boot-time port printk ARM: vexpress: add sched_clock() for Versatile Express ARM i.MX53: Make MX53 EVK bootable ARM i.MX53: Some bug fix about MX53 MSL code ARM: 6607/1: sa1100: Update platform device registration ARM: 6606/1: sa1100: Fix platform device registration ARM i.MX51: rename IPU irqs ARM i.MX51: Add ipu clock support ARM: imx/mx27_3ds: Add PMIC support ARM: DMA: Replace page_to_dma()/dma_to_page() with pfn_to_dma()/dma_to_pfn() mx51: fix usb clock support MX51: Add support for usb host 2 arch/arm/plat-mxc/ehci.c: fix errors/typos ...
Diffstat (limited to 'drivers/serial')
-rw-r--r--drivers/serial/amba-pl011.c592
1 files changed, 561 insertions, 31 deletions
diff --git a/drivers/serial/amba-pl011.c b/drivers/serial/amba-pl011.c
index 6ca7a44..e76d7d0 100644
--- a/drivers/serial/amba-pl011.c
+++ b/drivers/serial/amba-pl011.c
@@ -7,6 +7,7 @@
*
* Copyright 1999 ARM Limited
* Copyright (C) 2000 Deep Blue Solutions Ltd.
+ * Copyright (C) 2010 ST-Ericsson SA
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@@ -48,6 +49,9 @@
#include <linux/amba/serial.h>
#include <linux/clk.h>
#include <linux/slab.h>
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
+#include <linux/scatterlist.h>
#include <asm/io.h>
#include <asm/sizes.h>
@@ -63,21 +67,6 @@
#define UART_DR_ERROR (UART011_DR_OE|UART011_DR_BE|UART011_DR_PE|UART011_DR_FE)
#define UART_DUMMY_DR_RX (1 << 16)
-/*
- * We wrap our port structure around the generic uart_port.
- */
-struct uart_amba_port {
- struct uart_port port;
- struct clk *clk;
- unsigned int im; /* interrupt mask */
- unsigned int old_status;
- unsigned int ifls; /* vendor-specific */
- unsigned int lcrh_tx; /* vendor-specific */
- unsigned int lcrh_rx; /* vendor-specific */
- bool oversampling; /* vendor-specific */
- bool autorts;
-};
-
/* There is by now at least one vendor with differing details, so handle it */
struct vendor_data {
unsigned int ifls;
@@ -85,6 +74,7 @@ struct vendor_data {
unsigned int lcrh_tx;
unsigned int lcrh_rx;
bool oversampling;
+ bool dma_threshold;
};
static struct vendor_data vendor_arm = {
@@ -93,6 +83,7 @@ static struct vendor_data vendor_arm = {
.lcrh_tx = UART011_LCRH,
.lcrh_rx = UART011_LCRH,
.oversampling = false,
+ .dma_threshold = false,
};
static struct vendor_data vendor_st = {
@@ -101,22 +92,535 @@ static struct vendor_data vendor_st = {
.lcrh_tx = ST_UART011_LCRH_TX,
.lcrh_rx = ST_UART011_LCRH_RX,
.oversampling = true,
+ .dma_threshold = true,
+};
+
+/* Deals with DMA transactions */
+struct pl011_dmatx_data {
+ struct dma_chan *chan;
+ struct scatterlist sg;
+ char *buf;
+ bool queued;
};
+/*
+ * We wrap our port structure around the generic uart_port.
+ */
+struct uart_amba_port {
+ struct uart_port port;
+ struct clk *clk;
+ const struct vendor_data *vendor;
+ unsigned int dmacr; /* dma control reg */
+ unsigned int im; /* interrupt mask */
+ unsigned int old_status;
+ unsigned int fifosize; /* vendor-specific */
+ unsigned int lcrh_tx; /* vendor-specific */
+ unsigned int lcrh_rx; /* vendor-specific */
+ bool autorts;
+ char type[12];
+#ifdef CONFIG_DMA_ENGINE
+ /* DMA stuff */
+ bool using_dma;
+ struct pl011_dmatx_data dmatx;
+#endif
+};
+
+/*
+ * All the DMA operation mode stuff goes inside this ifdef.
+ * This assumes that you have a generic DMA device interface,
+ * no custom DMA interfaces are supported.
+ */
+#ifdef CONFIG_DMA_ENGINE
+
+#define PL011_DMA_BUFFER_SIZE PAGE_SIZE
+
+static void pl011_dma_probe_initcall(struct uart_amba_port *uap)
+{
+ /* DMA is the sole user of the platform data right now */
+ struct amba_pl011_data *plat = uap->port.dev->platform_data;
+ struct dma_slave_config tx_conf = {
+ .dst_addr = uap->port.mapbase + UART01x_DR,
+ .dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE,
+ .direction = DMA_TO_DEVICE,
+ .dst_maxburst = uap->fifosize >> 1,
+ };
+ struct dma_chan *chan;
+ dma_cap_mask_t mask;
+
+ /* We need platform data */
+ if (!plat || !plat->dma_filter) {
+ dev_info(uap->port.dev, "no DMA platform data\n");
+ return;
+ }
+
+ /* Try to acquire a generic DMA engine slave channel */
+ dma_cap_zero(mask);
+ dma_cap_set(DMA_SLAVE, mask);
+
+ chan = dma_request_channel(mask, plat->dma_filter, plat->dma_tx_param);
+ if (!chan) {
+ dev_err(uap->port.dev, "no TX DMA channel!\n");
+ return;
+ }
+
+ dmaengine_slave_config(chan, &tx_conf);
+ uap->dmatx.chan = chan;
+
+ dev_info(uap->port.dev, "DMA channel TX %s\n",
+ dma_chan_name(uap->dmatx.chan));
+}
+
+#ifndef MODULE
+/*
+ * Stack up the UARTs and let the above initcall be done at device
+ * initcall time, because the serial driver is called as an arch
+ * initcall, and at this time the DMA subsystem is not yet registered.
+ * At this point the driver will switch over to using DMA where desired.
+ */
+struct dma_uap {
+ struct list_head node;
+ struct uart_amba_port *uap;
+};
+
+static LIST_HEAD(pl011_dma_uarts);
+
+static int __init pl011_dma_initcall(void)
+{
+ struct list_head *node, *tmp;
+
+ list_for_each_safe(node, tmp, &pl011_dma_uarts) {
+ struct dma_uap *dmau = list_entry(node, struct dma_uap, node);
+ pl011_dma_probe_initcall(dmau->uap);
+ list_del(node);
+ kfree(dmau);
+ }
+ return 0;
+}
+
+device_initcall(pl011_dma_initcall);
+
+static void pl011_dma_probe(struct uart_amba_port *uap)
+{
+ struct dma_uap *dmau = kzalloc(sizeof(struct dma_uap), GFP_KERNEL);
+ if (dmau) {
+ dmau->uap = uap;
+ list_add_tail(&dmau->node, &pl011_dma_uarts);
+ }
+}
+#else
+static void pl011_dma_probe(struct uart_amba_port *uap)
+{
+ pl011_dma_probe_initcall(uap);
+}
+#endif
+
+static void pl011_dma_remove(struct uart_amba_port *uap)
+{
+ /* TODO: remove the initcall if it has not yet executed */
+ if (uap->dmatx.chan)
+ dma_release_channel(uap->dmatx.chan);
+}
+
+
+/* Forward declare this for the refill routine */
+static int pl011_dma_tx_refill(struct uart_amba_port *uap);
+
+/*
+ * The current DMA TX buffer has been sent.
+ * Try to queue up another DMA buffer.
+ */
+static void pl011_dma_tx_callback(void *data)
+{
+ struct uart_amba_port *uap = data;
+ struct pl011_dmatx_data *dmatx = &uap->dmatx;
+ unsigned long flags;
+ u16 dmacr;
+
+ spin_lock_irqsave(&uap->port.lock, flags);
+ if (uap->dmatx.queued)
+ dma_unmap_sg(dmatx->chan->device->dev, &dmatx->sg, 1,
+ DMA_TO_DEVICE);
+
+ dmacr = uap->dmacr;
+ uap->dmacr = dmacr & ~UART011_TXDMAE;
+ writew(uap->dmacr, uap->port.membase + UART011_DMACR);
+
+ /*
+ * If TX DMA was disabled, it means that we've stopped the DMA for
+ * some reason (eg, XOFF received, or we want to send an X-char.)
+ *
+ * Note: we need to be careful here of a potential race between DMA
+ * and the rest of the driver - if the driver disables TX DMA while
+ * a TX buffer completing, we must update the tx queued status to
+ * get further refills (hence we check dmacr).
+ */
+ if (!(dmacr & UART011_TXDMAE) || uart_tx_stopped(&uap->port) ||
+ uart_circ_empty(&uap->port.state->xmit)) {
+ uap->dmatx.queued = false;
+ spin_unlock_irqrestore(&uap->port.lock, flags);
+ return;
+ }
+
+ if (pl011_dma_tx_refill(uap) <= 0) {
+ /*
+ * We didn't queue a DMA buffer for some reason, but we
+ * have data pending to be sent. Re-enable the TX IRQ.
+ */
+ uap->im |= UART011_TXIM;
+ writew(uap->im, uap->port.membase + UART011_IMSC);
+ }
+ spin_unlock_irqrestore(&uap->port.lock, flags);
+}
+
+/*
+ * Try to refill the TX DMA buffer.
+ * Locking: called with port lock held and IRQs disabled.
+ * Returns:
+ * 1 if we queued up a TX DMA buffer.
+ * 0 if we didn't want to handle this by DMA
+ * <0 on error
+ */
+static int pl011_dma_tx_refill(struct uart_amba_port *uap)
+{
+ struct pl011_dmatx_data *dmatx = &uap->dmatx;
+ struct dma_chan *chan = dmatx->chan;
+ struct dma_device *dma_dev = chan->device;
+ struct dma_async_tx_descriptor *desc;
+ struct circ_buf *xmit = &uap->port.state->xmit;
+ unsigned int count;
+
+ /*
+ * Try to avoid the overhead involved in using DMA if the
+ * transaction fits in the first half of the FIFO, by using
+ * the standard interrupt handling. This ensures that we
+ * issue a uart_write_wakeup() at the appropriate time.
+ */
+ count = uart_circ_chars_pending(xmit);
+ if (count < (uap->fifosize >> 1)) {
+ uap->dmatx.queued = false;
+ return 0;
+ }
+
+ /*
+ * Bodge: don't send the last character by DMA, as this
+ * will prevent XON from notifying us to restart DMA.
+ */
+ count -= 1;
+
+ /* Else proceed to copy the TX chars to the DMA buffer and fire DMA */
+ if (count > PL011_DMA_BUFFER_SIZE)
+ count = PL011_DMA_BUFFER_SIZE;
+
+ if (xmit->tail < xmit->head)
+ memcpy(&dmatx->buf[0], &xmit->buf[xmit->tail], count);
+ else {
+ size_t first = UART_XMIT_SIZE - xmit->tail;
+ size_t second = xmit->head;
+
+ memcpy(&dmatx->buf[0], &xmit->buf[xmit->tail], first);
+ if (second)
+ memcpy(&dmatx->buf[first], &xmit->buf[0], second);
+ }
+
+ dmatx->sg.length = count;
+
+ if (dma_map_sg(dma_dev->dev, &dmatx->sg, 1, DMA_TO_DEVICE) != 1) {
+ uap->dmatx.queued = false;
+ dev_dbg(uap->port.dev, "unable to map TX DMA\n");
+ return -EBUSY;
+ }
+
+ desc = dma_dev->device_prep_slave_sg(chan, &dmatx->sg, 1, DMA_TO_DEVICE,
+ DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+ if (!desc) {
+ dma_unmap_sg(dma_dev->dev, &dmatx->sg, 1, DMA_TO_DEVICE);
+ uap->dmatx.queued = false;
+ /*
+ * If DMA cannot be used right now, we complete this
+ * transaction via IRQ and let the TTY layer retry.
+ */
+ dev_dbg(uap->port.dev, "TX DMA busy\n");
+ return -EBUSY;
+ }
+
+ /* Some data to go along to the callback */
+ desc->callback = pl011_dma_tx_callback;
+ desc->callback_param = uap;
+
+ /* All errors should happen at prepare time */
+ dmaengine_submit(desc);
+
+ /* Fire the DMA transaction */
+ dma_dev->device_issue_pending(chan);
+
+ uap->dmacr |= UART011_TXDMAE;
+ writew(uap->dmacr, uap->port.membase + UART011_DMACR);
+ uap->dmatx.queued = true;
+
+ /*
+ * Now we know that DMA will fire, so advance the ring buffer
+ * with the stuff we just dispatched.
+ */
+ xmit->tail = (xmit->tail + count) & (UART_XMIT_SIZE - 1);
+ uap->port.icount.tx += count;
+
+ if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+ uart_write_wakeup(&uap->port);
+
+ return 1;
+}
+
+/*
+ * We received a transmit interrupt without a pending X-char but with
+ * pending characters.
+ * Locking: called with port lock held and IRQs disabled.
+ * Returns:
+ * false if we want to use PIO to transmit
+ * true if we queued a DMA buffer
+ */
+static bool pl011_dma_tx_irq(struct uart_amba_port *uap)
+{
+ if (!uap->using_dma)
+ return false;
+
+ /*
+ * If we already have a TX buffer queued, but received a
+ * TX interrupt, it will be because we've just sent an X-char.
+ * Ensure the TX DMA is enabled and the TX IRQ is disabled.
+ */
+ if (uap->dmatx.queued) {
+ uap->dmacr |= UART011_TXDMAE;
+ writew(uap->dmacr, uap->port.membase + UART011_DMACR);
+ uap->im &= ~UART011_TXIM;
+ writew(uap->im, uap->port.membase + UART011_IMSC);
+ return true;
+ }
+
+ /*
+ * We don't have a TX buffer queued, so try to queue one.
+ * If we succesfully queued a buffer, mask the TX IRQ.
+ */
+ if (pl011_dma_tx_refill(uap) > 0) {
+ uap->im &= ~UART011_TXIM;
+ writew(uap->im, uap->port.membase + UART011_IMSC);
+ return true;
+ }
+ return false;
+}
+
+/*
+ * Stop the DMA transmit (eg, due to received XOFF).
+ * Locking: called with port lock held and IRQs disabled.
+ */
+static inline void pl011_dma_tx_stop(struct uart_amba_port *uap)
+{
+ if (uap->dmatx.queued) {
+ uap->dmacr &= ~UART011_TXDMAE;
+ writew(uap->dmacr, uap->port.membase + UART011_DMACR);
+ }
+}
+
+/*
+ * Try to start a DMA transmit, or in the case of an XON/OFF
+ * character queued for send, try to get that character out ASAP.
+ * Locking: called with port lock held and IRQs disabled.
+ * Returns:
+ * false if we want the TX IRQ to be enabled
+ * true if we have a buffer queued
+ */
+static inline bool pl011_dma_tx_start(struct uart_amba_port *uap)
+{
+ u16 dmacr;
+
+ if (!uap->using_dma)
+ return false;
+
+ if (!uap->port.x_char) {
+ /* no X-char, try to push chars out in DMA mode */
+ bool ret = true;
+
+ if (!uap->dmatx.queued) {
+ if (pl011_dma_tx_refill(uap) > 0) {
+ uap->im &= ~UART011_TXIM;
+ ret = true;
+ } else {
+ uap->im |= UART011_TXIM;
+ ret = false;
+ }
+ writew(uap->im, uap->port.membase + UART011_IMSC);
+ } else if (!(uap->dmacr & UART011_TXDMAE)) {
+ uap->dmacr |= UART011_TXDMAE;
+ writew(uap->dmacr,
+ uap->port.membase + UART011_DMACR);
+ }
+ return ret;
+ }
+
+ /*
+ * We have an X-char to send. Disable DMA to prevent it loading
+ * the TX fifo, and then see if we can stuff it into the FIFO.
+ */
+ dmacr = uap->dmacr;
+ uap->dmacr &= ~UART011_TXDMAE;
+ writew(uap->dmacr, uap->port.membase + UART011_DMACR);
+
+ if (readw(uap->port.membase + UART01x_FR) & UART01x_FR_TXFF) {
+ /*
+ * No space in the FIFO, so enable the transmit interrupt
+ * so we know when there is space. Note that once we've
+ * loaded the character, we should just re-enable DMA.
+ */
+ return false;
+ }
+
+ writew(uap->port.x_char, uap->port.membase + UART01x_DR);
+ uap->port.icount.tx++;
+ uap->port.x_char = 0;
+
+ /* Success - restore the DMA state */
+ uap->dmacr = dmacr;
+ writew(dmacr, uap->port.membase + UART011_DMACR);
+
+ return true;
+}
+
+/*
+ * Flush the transmit buffer.
+ * Locking: called with port lock held and IRQs disabled.
+ */
+static void pl011_dma_flush_buffer(struct uart_port *port)
+{
+ struct uart_amba_port *uap = (struct uart_amba_port *)port;
+
+ if (!uap->using_dma)
+ return;
+
+ /* Avoid deadlock with the DMA engine callback */
+ spin_unlock(&uap->port.lock);
+ dmaengine_terminate_all(uap->dmatx.chan);
+ spin_lock(&uap->port.lock);
+ if (uap->dmatx.queued) {
+ dma_unmap_sg(uap->dmatx.chan->device->dev, &uap->dmatx.sg, 1,
+ DMA_TO_DEVICE);
+ uap->dmatx.queued = false;
+ uap->dmacr &= ~UART011_TXDMAE;
+ writew(uap->dmacr, uap->port.membase + UART011_DMACR);
+ }
+}
+
+
+static void pl011_dma_startup(struct uart_amba_port *uap)
+{
+ if (!uap->dmatx.chan)
+ return;
+
+ uap->dmatx.buf = kmalloc(PL011_DMA_BUFFER_SIZE, GFP_KERNEL);
+ if (!uap->dmatx.buf) {
+ dev_err(uap->port.dev, "no memory for DMA TX buffer\n");
+ uap->port.fifosize = uap->fifosize;
+ return;
+ }
+
+ sg_init_one(&uap->dmatx.sg, uap->dmatx.buf, PL011_DMA_BUFFER_SIZE);
+
+ /* The DMA buffer is now the FIFO the TTY subsystem can use */
+ uap->port.fifosize = PL011_DMA_BUFFER_SIZE;
+ uap->using_dma = true;
+
+ /* Turn on DMA error (RX/TX will be enabled on demand) */
+ uap->dmacr |= UART011_DMAONERR;
+ writew(uap->dmacr, uap->port.membase + UART011_DMACR);
+
+ /*
+ * ST Micro variants has some specific dma burst threshold
+ * compensation. Set this to 16 bytes, so burst will only
+ * be issued above/below 16 bytes.
+ */
+ if (uap->vendor->dma_threshold)
+ writew(ST_UART011_DMAWM_RX_16 | ST_UART011_DMAWM_TX_16,
+ uap->port.membase + ST_UART011_DMAWM);
+}
+
+static void pl011_dma_shutdown(struct uart_amba_port *uap)
+{
+ if (!uap->using_dma)
+ return;
+
+ /* Disable RX and TX DMA */
+ while (readw(uap->port.membase + UART01x_FR) & UART01x_FR_BUSY)
+ barrier();
+
+ spin_lock_irq(&uap->port.lock);
+ uap->dmacr &= ~(UART011_DMAONERR | UART011_RXDMAE | UART011_TXDMAE);
+ writew(uap->dmacr, uap->port.membase + UART011_DMACR);
+ spin_unlock_irq(&uap->port.lock);
+
+ /* In theory, this should already be done by pl011_dma_flush_buffer */
+ dmaengine_terminate_all(uap->dmatx.chan);
+ if (uap->dmatx.queued) {
+ dma_unmap_sg(uap->dmatx.chan->device->dev, &uap->dmatx.sg, 1,
+ DMA_TO_DEVICE);
+ uap->dmatx.queued = false;
+ }
+
+ kfree(uap->dmatx.buf);
+
+ uap->using_dma = false;
+}
+
+#else
+/* Blank functions if the DMA engine is not available */
+static inline void pl011_dma_probe(struct uart_amba_port *uap)
+{
+}
+
+static inline void pl011_dma_remove(struct uart_amba_port *uap)
+{
+}
+
+static inline void pl011_dma_startup(struct uart_amba_port *uap)
+{
+}
+
+static inline void pl011_dma_shutdown(struct uart_amba_port *uap)
+{
+}
+
+static inline bool pl011_dma_tx_irq(struct uart_amba_port *uap)
+{
+ return false;
+}
+
+static inline void pl011_dma_tx_stop(struct uart_amba_port *uap)
+{
+}
+
+static inline bool pl011_dma_tx_start(struct uart_amba_port *uap)
+{
+ return false;
+}
+
+#define pl011_dma_flush_buffer NULL
+#endif
+
+
static void pl011_stop_tx(struct uart_port *port)
{
struct uart_amba_port *uap = (struct uart_amba_port *)port;
uap->im &= ~UART011_TXIM;
writew(uap->im, uap->port.membase + UART011_IMSC);
+ pl011_dma_tx_stop(uap);
}
static void pl011_start_tx(struct uart_port *port)
{
struct uart_amba_port *uap = (struct uart_amba_port *)port;
- uap->im |= UART011_TXIM;
- writew(uap->im, uap->port.membase + UART011_IMSC);
+ if (!pl011_dma_tx_start(uap)) {
+ uap->im |= UART011_TXIM;
+ writew(uap->im, uap->port.membase + UART011_IMSC);
+ }
}
static void pl011_stop_rx(struct uart_port *port)
@@ -203,7 +707,11 @@ static void pl011_tx_chars(struct uart_amba_port *uap)
return;
}
- count = uap->port.fifosize >> 1;
+ /* If we are using DMA mode, try to send some characters. */
+ if (pl011_dma_tx_irq(uap))
+ return;
+
+ count = uap->fifosize >> 1;
do {
writew(xmit->buf[xmit->tail], uap->port.membase + UART01x_DR);
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
@@ -246,10 +754,11 @@ static void pl011_modem_status(struct uart_amba_port *uap)
static irqreturn_t pl011_int(int irq, void *dev_id)
{
struct uart_amba_port *uap = dev_id;
+ unsigned long flags;
unsigned int status, pass_counter = AMBA_ISR_PASS_LIMIT;
int handled = 0;
- spin_lock(&uap->port.lock);
+ spin_lock_irqsave(&uap->port.lock, flags);
status = readw(uap->port.membase + UART011_MIS);
if (status) {
@@ -274,7 +783,7 @@ static irqreturn_t pl011_int(int irq, void *dev_id)
handled = 1;
}
- spin_unlock(&uap->port.lock);
+ spin_unlock_irqrestore(&uap->port.lock, flags);
return IRQ_RETVAL(handled);
}
@@ -396,7 +905,7 @@ static int pl011_startup(struct uart_port *port)
if (retval)
goto clk_dis;
- writew(uap->ifls, uap->port.membase + UART011_IFLS);
+ writew(uap->vendor->ifls, uap->port.membase + UART011_IFLS);
/*
* Provoke TX FIFO interrupt into asserting.
@@ -423,11 +932,18 @@ static int pl011_startup(struct uart_port *port)
cr = UART01x_CR_UARTEN | UART011_CR_RXE | UART011_CR_TXE;
writew(cr, uap->port.membase + UART011_CR);
+ /* Clear pending error interrupts */
+ writew(UART011_OEIS | UART011_BEIS | UART011_PEIS | UART011_FEIS,
+ uap->port.membase + UART011_ICR);
+
/*
* initialise the old status of the modem signals
*/
uap->old_status = readw(uap->port.membase + UART01x_FR) & UART01x_FR_MODEM_ANY;
+ /* Startup DMA */
+ pl011_dma_startup(uap);
+
/*
* Finally, enable interrupts
*/
@@ -467,6 +983,8 @@ static void pl011_shutdown(struct uart_port *port)
writew(0xffff, uap->port.membase + UART011_ICR);
spin_unlock_irq(&uap->port.lock);
+ pl011_dma_shutdown(uap);
+
/*
* Free the interrupt
*/
@@ -498,13 +1016,18 @@ pl011_set_termios(struct uart_port *port, struct ktermios *termios,
struct uart_amba_port *uap = (struct uart_amba_port *)port;
unsigned int lcr_h, old_cr;
unsigned long flags;
- unsigned int baud, quot;
+ unsigned int baud, quot, clkdiv;
+
+ if (uap->vendor->oversampling)
+ clkdiv = 8;
+ else
+ clkdiv = 16;
/*
* Ask the core to calculate the divisor for us.
*/
baud = uart_get_baud_rate(port, termios, old, 0,
- port->uartclk/(uap->oversampling ? 8 : 16));
+ port->uartclk / clkdiv);
if (baud > port->uartclk/16)
quot = DIV_ROUND_CLOSEST(port->uartclk * 8, baud);
@@ -532,7 +1055,7 @@ pl011_set_termios(struct uart_port *port, struct ktermios *termios,
if (!(termios->c_cflag & PARODD))
lcr_h |= UART01x_LCRH_EPS;
}
- if (port->fifosize > 1)
+ if (uap->fifosize > 1)
lcr_h |= UART01x_LCRH_FEN;
spin_lock_irqsave(&port->lock, flags);
@@ -588,8 +1111,8 @@ pl011_set_termios(struct uart_port *port, struct ktermios *termios,
uap->autorts = false;
}
- if (uap->oversampling) {
- if (baud > port->uartclk/16)
+ if (uap->vendor->oversampling) {
+ if (baud > port->uartclk / 16)
old_cr |= ST_UART011_CR_OVSFACT;
else
old_cr &= ~ST_UART011_CR_OVSFACT;
@@ -622,7 +1145,8 @@ pl011_set_termios(struct uart_port *port, struct ktermios *termios,
static const char *pl011_type(struct uart_port *port)
{
- return port->type == PORT_AMBA ? "AMBA/PL011" : NULL;
+ struct uart_amba_port *uap = (struct uart_amba_port *)port;
+ return uap->port.type == PORT_AMBA ? uap->type : NULL;
}
/*
@@ -679,6 +1203,7 @@ static struct uart_ops amba_pl011_pops = {
.break_ctl = pl011_break_ctl,
.startup = pl011_startup,
.shutdown = pl011_shutdown,
+ .flush_buffer = pl011_dma_flush_buffer,
.set_termios = pl011_set_termios,
.type = pl011_type,
.release_port = pl010_release_port,
@@ -761,7 +1286,7 @@ pl011_console_get_options(struct uart_amba_port *uap, int *baud,
*baud = uap->port.uartclk * 4 / (64 * ibrd + fbrd);
- if (uap->oversampling) {
+ if (uap->vendor->oversampling) {
if (readw(uap->port.membase + UART011_CR)
& ST_UART011_CR_OVSFACT)
*baud *= 2;
@@ -858,19 +1383,22 @@ static int pl011_probe(struct amba_device *dev, struct amba_id *id)
goto unmap;
}
- uap->ifls = vendor->ifls;
+ uap->vendor = vendor;
uap->lcrh_rx = vendor->lcrh_rx;
uap->lcrh_tx = vendor->lcrh_tx;
- uap->oversampling = vendor->oversampling;
+ uap->fifosize = vendor->fifosize;
uap->port.dev = &dev->dev;
uap->port.mapbase = dev->res.start;
uap->port.membase = base;
uap->port.iotype = UPIO_MEM;
uap->port.irq = dev->irq[0];
- uap->port.fifosize = vendor->fifosize;
+ uap->port.fifosize = uap->fifosize;
uap->port.ops = &amba_pl011_pops;
uap->port.flags = UPF_BOOT_AUTOCONF;
uap->port.line = i;
+ pl011_dma_probe(uap);
+
+ snprintf(uap->type, sizeof(uap->type), "PL011 rev%u", amba_rev(dev));
amba_ports[i] = uap;
@@ -879,6 +1407,7 @@ static int pl011_probe(struct amba_device *dev, struct amba_id *id)
if (ret) {
amba_set_drvdata(dev, NULL);
amba_ports[i] = NULL;
+ pl011_dma_remove(uap);
clk_put(uap->clk);
unmap:
iounmap(base);
@@ -902,6 +1431,7 @@ static int pl011_remove(struct amba_device *dev)
if (amba_ports[i] == uap)
amba_ports[i] = NULL;
+ pl011_dma_remove(uap);
iounmap(uap->port.membase);
clk_put(uap->clk);
kfree(uap);
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