From: govindraj.raja@ti.com (Govindraj.R)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH v6 11/16] OMAP2+: UART: Move errata handling from serial.c to omap-serial
Date: Fri, 30 Sep 2011 16:32:36 +0530 [thread overview]
Message-ID: <1317380561-661-2-git-send-email-govindraj.raja@ti.com> (raw)
In-Reply-To: <1317380561-661-1-git-send-email-govindraj.raja@ti.com>
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@linux.intel.com>
Signed-off-by: Govindraj.R <govindraj.raja@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 ccf3550..0731575 100644
--- a/arch/arm/mach-omap2/serial.c
+++ b/arch/arm/mach-omap2/serial.c
@@ -42,8 +42,6 @@
#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
@@ -54,11 +52,6 @@
#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)
@@ -97,63 +90,6 @@ struct omap_hwmod *omap_uart_hwmod_lookup(int num)
#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);
-}
-
int omap_uart_can_sleep(void)
{
struct omap_hwmod *oh;
@@ -313,7 +249,20 @@ 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 */
@@ -388,6 +337,7 @@ 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
next prev parent reply other threads:[~2011-09-30 11:02 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-09-30 11:02 [PATCH v6 10/16] OMAP2+: UART: Modify omap_uart_can_sleep function Govindraj.R
2011-09-30 11:02 ` Govindraj.R [this message]
2011-10-11 21:01 ` [PATCH v6 11/16] OMAP2+: UART: Move errata handling from serial.c to omap-serial Kevin Hilman
2011-10-12 10:43 ` Govindraj
2011-09-30 11:02 ` [PATCH v6 12/16] OMAP2+: UART: Allow UART parameters to be configured from board file Govindraj.R
2011-10-11 18:53 ` Kevin Hilman
2011-10-12 10:44 ` Govindraj
2011-09-30 11:02 ` [PATCH v6 13/16] OMAP2+: UART: Make the RX_TIMEOUT for DMA configurable for each UART Govindraj.R
2011-09-30 11:02 ` [PATCH v6 14/16] OMAP2+: UART: Take console_lock in suspend path if not taken Govindraj.R
2011-10-11 19:01 ` Kevin Hilman
2011-10-12 11:23 ` Govindraj
2011-10-12 23:47 ` Kevin Hilman
2011-10-13 1:11 ` Govindraj
2011-09-30 11:02 ` [PATCH v6 15/16] OMAP2+: UART: Enable back uart clocks with runtime API for early console Govindraj.R
2011-10-11 21:06 ` Kevin Hilman
2011-10-12 14:04 ` Govindraj
2011-10-13 0:00 ` Kevin Hilman
2011-10-13 1:22 ` Govindraj
2011-10-13 21:01 ` Kevin Hilman
2011-10-14 14:18 ` Govindraj
2011-10-14 17:12 ` Kevin Hilman
2011-09-30 11:02 ` [PATCH v6 16/16] OMAP2+: UART: Do not gate uart clocks if used for debug_prints Govindraj.R
2011-10-11 18:24 ` [PATCH v6 10/16] OMAP2+: UART: Modify omap_uart_can_sleep function Kevin Hilman
2011-10-12 13:38 ` Govindraj
2011-10-12 19:41 ` Kevin Hilman
2011-10-13 1:09 ` Govindraj
2011-10-13 6:59 ` Jean Pihet
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