1
0
Fork 0

serial: omap: drop DMA support

The current support is known to be broken and
a later patch will come re-adding it using
dma engine API.

Tested-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
hifive-unleashed-5.1
Felipe Balbi 2012-09-06 15:45:21 +03:00 committed by Greg Kroah-Hartman
parent d8ee4ea68f
commit 4945743047
1 changed files with 12 additions and 318 deletions

View File

@ -33,7 +33,6 @@
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/io.h>
#include <linux/dma-mapping.h>
#include <linux/clk.h>
#include <linux/serial_core.h>
#include <linux/irq.h>
@ -41,7 +40,6 @@
#include <linux/of.h>
#include <linux/gpio.h>
#include <plat/dma.h>
#include <plat/dmtimer.h>
#include <plat/omap-serial.h>
@ -75,9 +73,6 @@
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;
@ -161,19 +156,6 @@ 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);
@ -189,22 +171,6 @@ 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) {
@ -212,8 +178,7 @@ 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);
@ -224,8 +189,6 @@ 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);
@ -343,67 +306,12 @@ 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)
@ -456,16 +364,8 @@ 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);
@ -616,20 +516,6 @@ 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
@ -677,17 +563,6 @@ 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);
@ -814,8 +689,6 @@ 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
@ -891,14 +764,9 @@ 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);
@ -1267,149 +1135,6 @@ 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;
@ -1479,7 +1204,7 @@ 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;
@ -1504,14 +1229,6 @@ 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;
if (gpio_is_valid(omap_up_info->DTR_gpio) &&
omap_up_info->DTR_present) {
ret = gpio_request(omap_up_info->DTR_gpio, "omap-serial");
@ -1574,20 +1291,6 @@ 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;
@ -1730,10 +1433,6 @@ 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);
@ -1751,11 +1450,6 @@ 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);
}