[PATCH v5 10/15] OMAP2+: UART: Move errata handling from serial.c to omap-serial
Govindraj.R
govindraj.raja at ti.com
Wed Sep 21 08:13:47 EDT 2011
Move the errata handling mechanism from serial.c to omap-serial file
and utilise the same func in driver file.
Errata i202, i291 are moved to be handled with omap-serial
Moving the errata macro from serial.c file to driver header file
as from on errata will be handled in driver file itself.
Corrected errata id from chapter reference 2.15 to errata id i291.
Acked-by: Alan Cox <alan at linux.intel.com>
Signed-off-by: Govindraj.R <govindraj.raja at ti.com>
---
arch/arm/mach-omap2/serial.c | 78 +++++--------------------
arch/arm/plat-omap/include/plat/omap-serial.h | 5 ++
drivers/tty/serial/omap-serial.c | 63 ++++++++++++++++++--
3 files changed, 77 insertions(+), 69 deletions(-)
diff --git a/arch/arm/mach-omap2/serial.c b/arch/arm/mach-omap2/serial.c
index 43d8f0d..9fe248e 100644
--- a/arch/arm/mach-omap2/serial.c
+++ b/arch/arm/mach-omap2/serial.c
@@ -41,8 +41,6 @@
#include "control.h"
#include "mux.h"
-#define UART_ERRATA_i202_MDR1_ACCESS (0x1 << 1)
-
/*
* NOTE: By default the serial timeout is disabled as it causes lost characters
* over the serial ports. This means that the UART clocks will stay on until
@@ -53,11 +51,6 @@
#define MAX_UART_HWMOD_NAME_LEN 16
-struct omap_uart_state {
- int num;
- u32 dma_enabled;
-};
-
static u8 num_uarts;
static int uart_idle_hwmod(struct omap_device *od)
@@ -84,63 +77,6 @@ static struct omap_device_pm_latency omap_uart_latency[] = {
#if defined(CONFIG_PM)
-/*
- * Work Around for Errata i202 (3430 - 1.12, 3630 - 1.6)
- * The access to uart register after MDR1 Access
- * causes UART to corrupt data.
- *
- * Need a delay =
- * 5 L4 clock cycles + 5 UART functional clock cycle (@48MHz = ~0.2uS)
- * give 10 times as much
- */
-static void omap_uart_mdr1_errataset(struct omap_uart_state *uart, u8 mdr1_val,
- u8 fcr_val)
-{
- u8 timeout = 255;
-
- serial_write_reg(uart, UART_OMAP_MDR1, mdr1_val);
- udelay(2);
- serial_write_reg(uart, UART_FCR, fcr_val | UART_FCR_CLEAR_XMIT |
- UART_FCR_CLEAR_RCVR);
- /*
- * Wait for FIFO to empty: when empty, RX_FIFO_E bit is 0 and
- * TX_FIFO_E bit is 1.
- */
- while (UART_LSR_THRE != (serial_read_reg(uart, UART_LSR) &
- (UART_LSR_THRE | UART_LSR_DR))) {
- timeout--;
- if (!timeout) {
- /* Should *never* happen. we warn and carry on */
- dev_crit(&uart->pdev->dev, "Errata i202: timedout %x\n",
- serial_read_reg(uart, UART_LSR));
- break;
- }
- udelay(1);
- }
-}
-#endif /* CONFIG_PM && CONFIG_ARCH_OMAP3 */
-
-static void omap_uart_smart_idle_enable(struct omap_uart_state *uart,
- int enable)
-{
- u8 idlemode;
-
- if (enable) {
- /**
- * Errata 2.15: [UART]:Cannot Acknowledge Idle Requests
- * in Smartidle Mode When Configured for DMA Operations.
- */
- if (uart->dma_enabled)
- idlemode = HWMOD_IDLEMODE_FORCE;
- else
- idlemode = HWMOD_IDLEMODE_SMART;
- } else {
- idlemode = HWMOD_IDLEMODE_NO;
- }
-
- omap_hwmod_set_slave_idlemode(uart->oh, idlemode);
-}
-
#ifdef CONFIG_OMAP_MUX
static struct omap_device_pad default_uart1_pads[] __initdata = {
{
@@ -282,7 +218,20 @@ static void omap_uart_enable_wakeup(struct platform_device *pdev, bool enable)
omap_hwmod_disable_wakeup(od->hwmods[0]);
}
+/*
+ * Errata i291: [UART]:Cannot Acknowledge Idle Requests
+ * in Smartidle Mode When Configured for DMA Operations.
+ * WA: configure uart in force idle mode.
+ */
+static void omap_uart_set_forceidle(struct platform_device *pdev)
+{
+ struct omap_device *od = to_omap_device(pdev);
+
+ omap_hwmod_set_slave_idlemode(od->hwmods[0], HWMOD_IDLEMODE_FORCE);
+}
+
#else
+static void omap_uart_set_forceidle(struct platform_device *pdev) {}
static void omap_uart_enable_wakeup(struct platform_device *pdev, bool enable)
{}
#endif /* CONFIG_PM */
@@ -369,6 +318,7 @@ void __init omap_serial_init_port(struct omap_board_data *bdata)
pdata->flags = UPF_BOOT_AUTOCONF;
pdata->enable_wakeup = omap_uart_enable_wakeup;
pdata->get_context_loss_count = omap_pm_get_dev_context_loss_count;
+ pdata->set_force_idle = omap_uart_set_forceidle;
/* Enable the MDR1 errata for OMAP3 */
if (cpu_is_omap34xx() && !cpu_is_ti816x())
diff --git a/arch/arm/plat-omap/include/plat/omap-serial.h b/arch/arm/plat-omap/include/plat/omap-serial.h
index 8ef81ce..12f5262 100644
--- a/arch/arm/plat-omap/include/plat/omap-serial.h
+++ b/arch/arm/plat-omap/include/plat/omap-serial.h
@@ -56,6 +56,8 @@
#define MSR_SAVE_FLAGS UART_MSR_ANY_DELTA
+#define UART_ERRATA_i202_MDR1_ACCESS (0x1 << 1)
+
struct omap_uart_port_info {
bool dma_enabled; /* To specify DMA Mode */
unsigned int uartclk; /* UART clock rate */
@@ -65,6 +67,7 @@ struct omap_uart_port_info {
void (*enable_wakeup)(struct platform_device *, bool);
u32 (*get_context_loss_count)(struct device *);
+ void (*set_force_idle)(struct platform_device *);
};
struct uart_omap_dma {
@@ -118,6 +121,8 @@ struct uart_omap_port {
unsigned long port_activity;
u32 context_loss_cnt;
u8 wakeups_enabled;
+ u32 errata;
+
};
#endif /* __OMAP_SERIAL_H__ */
diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
index 43c33da..817443e 100644
--- a/drivers/tty/serial/omap-serial.c
+++ b/drivers/tty/serial/omap-serial.c
@@ -51,6 +51,7 @@ static struct uart_omap_port *ui[OMAP_MAX_HSUART_PORTS];
static void uart_tx_dma_callback(int lch, u16 ch_status, void *data);
static void serial_omap_rx_timeout(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 inline unsigned int serial_in(struct uart_omap_port *up, int offset)
{
@@ -805,7 +806,11 @@ serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
/* Protocol, Baud Rate, and Interrupt Settings */
- serial_out(up, UART_OMAP_MDR1, up->mdr1);
+ if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
+ serial_omap_mdr1_errataset(up, up->mdr1);
+ else
+ serial_out(up, UART_OMAP_MDR1, up->mdr1);
+
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
up->efr = serial_in(up, UART_EFR);
@@ -830,7 +835,10 @@ serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
else
up->mdr1 = UART_OMAP_MDR1_16X_MODE;
- serial_out(up, UART_OMAP_MDR1, up->mdr1);
+ if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
+ serial_omap_mdr1_errataset(up, up->mdr1);
+ else
+ serial_out(up, UART_OMAP_MDR1, up->mdr1);
/* Hardware Flow Control Configuration */
@@ -1350,6 +1358,7 @@ static int serial_omap_probe(struct platform_device *pdev)
up->port.flags = omap_up_info->flags;
up->port.uartclk = omap_up_info->uartclk;
up->uart_dma.uart_base = mem->start;
+ up->errata = omap_up_info->errata;
if (omap_up_info->dma_enabled) {
up->uart_dma.uart_dma_tx = dma_tx->start;
@@ -1405,9 +1414,47 @@ static int serial_omap_remove(struct platform_device *dev)
return 0;
}
+/*
+ * Work Around for Errata i202 (3430 - 1.12, 3630 - 1.6)
+ * The access to uart register after MDR1 Access
+ * causes UART to corrupt data.
+ *
+ * Need a delay =
+ * 5 L4 clock cycles + 5 UART functional clock cycle (@48MHz = ~0.2uS)
+ * give 10 times as much
+ */
+static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1)
+{
+ u8 timeout = 255;
+
+ serial_out(up, UART_OMAP_MDR1, mdr1);
+ udelay(2);
+ serial_out(up, UART_FCR, up->fcr | UART_FCR_CLEAR_XMIT |
+ UART_FCR_CLEAR_RCVR);
+ /*
+ * Wait for FIFO to empty: when empty, RX_FIFO_E bit is 0 and
+ * TX_FIFO_E bit is 1.
+ */
+ while (UART_LSR_THRE != (serial_in(up, UART_LSR) &
+ (UART_LSR_THRE | UART_LSR_DR))) {
+ timeout--;
+ if (!timeout) {
+ /* Should *never* happen. we warn and carry on */
+ dev_crit(&up->pdev->dev, "Errata i202: timedout %x\n",
+ serial_in(up, UART_LSR));
+ break;
+ }
+ udelay(1);
+ }
+}
+
static void serial_omap_restore_context(struct uart_omap_port *up)
{
- serial_out(up, UART_OMAP_MDR1, up->mdr1);
+ if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
+ serial_omap_mdr1_errataset(up, UART_OMAP_MDR1_DISABLE);
+ else
+ serial_out(up, UART_OMAP_MDR1, UART_OMAP_MDR1_DISABLE);
+
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
serial_out(up, UART_EFR, UART_EFR_ECB);
serial_out(up, UART_LCR, 0x0); /* Operational mode */
@@ -1423,8 +1470,10 @@ static void serial_omap_restore_context(struct uart_omap_port *up)
serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
serial_out(up, UART_EFR, up->efr);
serial_out(up, UART_LCR, up->lcr);
- /* UART 16x mode */
- serial_out(up, UART_OMAP_MDR1, up->mdr1);
+ if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
+ serial_omap_mdr1_errataset(up, up->mdr1);
+ else
+ serial_out(up, UART_OMAP_MDR1, up->mdr1);
}
static int serial_omap_runtime_suspend(struct device *dev)
@@ -1453,6 +1502,10 @@ static int serial_omap_runtime_suspend(struct device *dev)
}
}
+ /* Errata i291 */
+ if (up->use_dma && pdata->set_force_idle)
+ pdata->set_force_idle(up->pdev);
+
return 0;
}
--
1.7.4.1
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