diff options
-rw-r--r-- | arch/arm/mach-omap2/serial.c | 101 | ||||
-rw-r--r-- | arch/arm/plat-omap/include/plat/omap-serial.h | 7 | ||||
-rw-r--r-- | drivers/tty/serial/omap-serial.c | 68 |
3 files changed, 102 insertions, 74 deletions
diff --git a/arch/arm/mach-omap2/serial.c b/arch/arm/mach-omap2/serial.c index 78ca7e8fc10..77a25cb1dcc 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 @@ -61,59 +59,17 @@ struct omap_uart_state { void __iomem *wk_st; void __iomem *wk_en; u32 wk_mask; - u32 dma_enabled; int clocked; struct list_head node; struct omap_hwmod *oh; struct platform_device *pdev; - - u32 errata; }; static LIST_HEAD(uart_list); static u8 num_uarts; -#if defined(CONFIG_PM) && defined(CONFIG_ARCH_OMAP3) - -/* - * 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 inline void omap_uart_enable_clocks(struct omap_uart_state *uart) { if (uart->clocked) @@ -156,27 +112,6 @@ static void omap_uart_disable_wakeup(struct omap_uart_state *uart) } } -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); -} - static void omap_uart_block_sleep(struct omap_uart_state *uart) { omap_uart_enable_clocks(uart); @@ -267,7 +202,28 @@ static void omap_uart_idle_init(struct omap_uart_state *uart) } } +/* + * 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_noidle(struct platform_device *pdev) +{ + struct omap_device *od = to_omap_device(pdev); + + omap_hwmod_set_slave_idlemode(od->hwmods[0], HWMOD_IDLEMODE_NO); +} + +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_noidle(struct platform_device *pdev) {} +static void omap_uart_set_forceidle(struct platform_device *pdev) {} static void omap_uart_block_sleep(struct omap_uart_state *uart) { /* Needed to enable UART clocks when built without CONFIG_PM */ @@ -473,13 +429,22 @@ void __init omap_serial_init_port(struct omap_board_data *bdata) break; oh = uart->oh; - uart->dma_enabled = 0; name = DRIVER_NAME; omap_up.dma_enabled = uart->dma_enabled; omap_up.uartclk = OMAP24XX_BASE_BAUD * 16; omap_up.flags = UPF_BOOT_AUTOCONF; omap_up.get_context_loss_count = omap_pm_get_dev_context_loss_count; + omap_up.set_forceidle = omap_uart_set_forceidle; + omap_up.set_noidle = omap_uart_set_noidle; + + /* Enable the MDR1 Errata i202 for OMAP2430/3xxx/44xx */ + if (!cpu_is_omap2420() && !cpu_is_ti816x()) + omap_up.errata |= UART_ERRATA_i202_MDR1_ACCESS; + + /* Enable DMA Mode Force Idle Errata i291 for omap34xx/3630 */ + if (cpu_is_omap34xx() || cpu_is_omap3630()) + omap_up.errata |= UART_ERRATA_i291_DMA_FORCEIDLE; pdata = &omap_up; pdata_size = sizeof(struct omap_uart_port_info); @@ -519,10 +484,6 @@ void __init omap_serial_init_port(struct omap_board_data *bdata) if (((cpu_is_omap34xx() || cpu_is_omap44xx()) && bdata->pads) || (pdata->wk_en && pdata->wk_mask)) device_init_wakeup(&pdev->dev, true); - - /* Enable the MDR1 errata for OMAP3 */ - if (cpu_is_omap34xx() && !(cpu_is_ti81xx() || cpu_is_am33xx())) - uart->errata |= UART_ERRATA_i202_MDR1_ACCESS; } /** diff --git a/arch/arm/plat-omap/include/plat/omap-serial.h b/arch/arm/plat-omap/include/plat/omap-serial.h index 348c9ead6ed..842b429cfea 100644 --- a/arch/arm/plat-omap/include/plat/omap-serial.h +++ b/arch/arm/plat-omap/include/plat/omap-serial.h @@ -58,12 +58,18 @@ #define MSR_SAVE_FLAGS UART_MSR_ANY_DELTA +#define UART_ERRATA_i202_MDR1_ACCESS BIT(0) +#define UART_ERRATA_i291_DMA_FORCEIDLE BIT(1) + struct omap_uart_port_info { bool dma_enabled; /* To specify DMA Mode */ unsigned int uartclk; /* UART clock rate */ upf_t flags; /* UPF_* flags */ + u32 errata; int (*get_context_loss_count)(struct device *); + void (*set_forceidle)(struct platform_device *); + void (*set_noidle)(struct platform_device *); }; struct uart_omap_dma { @@ -117,6 +123,7 @@ struct uart_omap_port { char name[20]; unsigned long port_activity; u32 context_loss_cnt; + u32 errata; }; #endif /* __OMAP_SERIAL_H__ */ diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c index ea4c24aa8c8..764ac779569 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) { @@ -808,7 +809,11 @@ 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); @@ -833,7 +838,10 @@ 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 */ @@ -1362,6 +1370,7 @@ 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; @@ -1415,9 +1424,47 @@ static int serial_omap_remove(struct platform_device *dev) return 0; } +/* + * Work Around for Errata i202 (2430, 3430, 3630, 4430 and 4460) + * 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, UART_OMAP_MDR1_DISABLE); + 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 */ @@ -1434,7 +1481,10 @@ static void serial_omap_restore_context(struct uart_omap_port *up) serial_out(up, UART_OMAP_SCR, up->scr); serial_out(up, UART_EFR, up->efr); serial_out(up, UART_LCR, up->lcr); - 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); } #ifdef CONFIG_PM_RUNTIME @@ -1449,6 +1499,11 @@ static int serial_omap_runtime_suspend(struct device *dev) if (pdata->get_context_loss_count) up->context_loss_cnt = pdata->get_context_loss_count(dev); + /* Errata i291 */ + if (up->use_dma && pdata->set_forceidle && + (up->errata & UART_ERRATA_i291_DMA_FORCEIDLE)) + pdata->set_forceidle(up->pdev); + return 0; } @@ -1464,6 +1519,11 @@ 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->use_dma && pdata->set_noidle && + (up->errata & UART_ERRATA_i291_DMA_FORCEIDLE)) + pdata->set_noidle(up->pdev); } return 0; |