"Govindraj.R" <[email protected]> writes: > Adapts omap-serial driver to use pm_runtime api's. > > 1.) Populate reg values to uart port which can be used for context restore. > 2.) Moved Erratum handling func to driver from serial.c > 3.) adding port_enable/disable func to enable/disable given uart port. > 4.) using prepare/resume api's to cut and enable back uart func_clks. > 5.) using timer to set flag to cut uart clocks based on this flag in > sram_idle path.
At least the errata handling should be in a separate patch as it's not related to runtime PM. Also, please be sure to test building this driver as a module. Because of direct access to hwmod in this patch, it will currently build as a module. > Signed-off-by: Govindraj.R <[email protected]> > --- > drivers/tty/serial/omap-serial.c | 304 > +++++++++++++++++++++++++++++++++++--- > 1 files changed, 283 insertions(+), 21 deletions(-) > > diff --git a/drivers/tty/serial/omap-serial.c > b/drivers/tty/serial/omap-serial.c > index d40924a..bc877b9 100644 > --- a/drivers/tty/serial/omap-serial.c > +++ b/drivers/tty/serial/omap-serial.c > @@ -33,10 +33,21 @@ > #include <linux/clk.h> > #include <linux/serial_core.h> > #include <linux/irq.h> > +#include <linux/pm_runtime.h> > > #include <plat/dma.h> > #include <plat/dmtimer.h> > #include <plat/omap-serial.h> > +#include <plat/serial.h> > +#include <plat/omap_device.h> > + > +#ifdef CONFIG_SERIAL_OMAP_CONSOLE > +#define omap_uart_console(port) ((port)->cons && (port)->cons->index == > (port)->line) > +#else > +#define omap_uart_console(port) NULL > +#endif > + > +#define OMAP_UART_CLK_PUT_DELAY (5 * HZ) > > static struct uart_omap_port *ui[OMAP_MAX_HSUART_PORTS]; > > @@ -44,6 +55,7 @@ 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 omap_uart_mdr1_errataset(struct uart_omap_port *up); > > static inline unsigned int serial_in(struct uart_omap_port *up, int offset) > { > @@ -90,6 +102,73 @@ serial_omap_get_divisor(struct uart_port *port, unsigned > int baud) > return port->uartclk/(baud * divisor); > } > > +static void omap_uart_smart_idle(struct uart_omap_port *up) > +{ > + struct platform_device *pdev = up->pdev; > + struct omap_device *od = container_of(pdev, struct omap_device, pdev); > + > + omap_hwmod_set_slave_idlemode(od->hwmods[0], HWMOD_IDLEMODE_SMART); > +} > + > +static void serial_omap_port_disable(struct uart_omap_port *up) > +{ > + if (!pm_runtime_suspended(&up->pdev->dev)) { > + del_timer(&up->inactivity_timer); > + if (omap_uart_console(&up->port)) > + console_stop(up->port.cons); > + > + pm_runtime_put_sync(&up->pdev->dev); > + } > +} This function should not be needed. The timer should be replaced by the auto-suspend feature of runtime PM. Instead of calling omap_port_disable() callers should call pm_runtime_put_autosuspend(), and the console_stop() should be part of the ->runtime_suspend() callback. Also, why do you check for pm_runtime_suspended()? Just call it for every time and we get runtime PM use-counting and statistics for free and the ->runtime_suspend() callback will be called when the usecount goes to zero. > +static void serial_omap_inactivity_timer(unsigned long uart_no) > +{ > + struct uart_omap_port *up = ui[uart_no]; > + > + up->can_sleep = 1; > + omap_uart_smart_idle(up); > +} This will not be needed if using the autosuspend feature. > +static void serial_omap_port_enable(struct uart_omap_port *up) > +{ > + if (pm_runtime_suspended(&up->pdev->dev)) { > + if (omap_uart_console(&up->port)) > + console_start(up->port.cons); > + > + pm_runtime_get_sync(&up->pdev->dev); > + } > + > + up->can_sleep = 0; > + mod_timer(&up->inactivity_timer, jiffies + OMAP_UART_CLK_PUT_DELAY); > +} Similarily to the disable side, callers of this function should call pm_runtime_get_sync() and the console_start() should be in the ->runtime_resume method. Again, no need to check pm_runtime_suspended() since the runtime PM core does usecounting already. > +void omap_uart_prepare_idle(int num) > +{ > + struct uart_omap_port *up = ui[num]; > + > + if (up && up->can_sleep) > + serial_omap_port_disable(up); pm_runtime_put_autosuspend() > +} > + > +void omap_uart_resume_idle(int num) > +{ > + struct uart_omap_port *up = ui[num]; > + struct omap_device *od; > + struct platform_device *pdev; > + > + if (!up) > + return; > + > + pdev = up->pdev; > + od = container_of(pdev, struct omap_device, pdev); od = to_omap_device(pdev); > + if (omap_hmwod_pad_wakeup_status(od->hwmods[0]) == true) > + serial_omap_port_enable(up); > + > + if (up->wk_st && (__raw_readl(up->wk_st) & up->wk_mask)) > + serial_omap_port_enable(up); > +} c.f. comments from PATCH 2/7 Also, direct hwmod access and PRCM accesses do not belong in drivers. Until it is understood why wakeups are not working, these hacks should stay in mach-omap2/serial.c > static void serial_omap_stop_rxdma(struct uart_omap_port *up) > { > if (up->uart_dma.rx_dma_used) { > @@ -105,6 +184,7 @@ static void serial_omap_enable_ms(struct uart_port *port) > { > struct uart_omap_port *up = (struct uart_omap_port *)port; > > + serial_omap_port_enable(up); pm_runtime_put_autosuspend() similarily for all calls to omap_port_enable() > dev_dbg(up->port.dev, "serial_omap_enable_ms+%d\n", up->pdev->id); > up->ier |= UART_IER_MSI; > serial_out(up, UART_IER, up->ier); > @@ -114,6 +194,7 @@ static void serial_omap_stop_tx(struct uart_port *port) > { > struct uart_omap_port *up = (struct uart_omap_port *)port; > > + serial_omap_port_enable(up); > if (up->use_dma && > up->uart_dma.tx_dma_channel != OMAP_UART_DMA_CH_FREE) { > /* > @@ -137,6 +218,7 @@ static void serial_omap_stop_rx(struct uart_port *port) > { > struct uart_omap_port *up = (struct uart_omap_port *)port; > > + serial_omap_port_enable(up); > if (up->use_dma) > serial_omap_stop_rxdma(up); > up->ier &= ~UART_IER_RLSI; > @@ -258,6 +340,7 @@ static void serial_omap_start_tx(struct uart_port *port) > unsigned int start; > int ret = 0; > > + serial_omap_port_enable(up); > if (!up->use_dma) { > serial_omap_enable_ier_thri(up); > return; > @@ -351,6 +434,7 @@ static inline irqreturn_t serial_omap_irq(int irq, void > *dev_id) > unsigned int iir, lsr; > unsigned long flags; > > + serial_omap_port_enable(up); > iir = serial_in(up, UART_IIR); > if (iir & UART_IIR_NO_INT) > return IRQ_NONE; > @@ -385,6 +469,7 @@ static unsigned int serial_omap_tx_empty(struct uart_port > *port) > unsigned long flags = 0; > unsigned int ret = 0; > > + serial_omap_port_enable(up); > dev_dbg(up->port.dev, "serial_omap_tx_empty+%d\n", up->pdev->id); > spin_lock_irqsave(&up->port.lock, flags); > ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0; > @@ -399,6 +484,7 @@ static unsigned int serial_omap_get_mctrl(struct > uart_port *port) > unsigned char status; > unsigned int ret = 0; > > + serial_omap_port_enable(up); > status = check_modem_status(up); > dev_dbg(up->port.dev, "serial_omap_get_mctrl+%d\n", up->pdev->id); > > @@ -419,6 +505,7 @@ static void serial_omap_set_mctrl(struct uart_port *port, > unsigned int mctrl) > unsigned char mcr = 0; > > dev_dbg(up->port.dev, "serial_omap_set_mctrl+%d\n", up->pdev->id); > + serial_omap_port_enable(up); > if (mctrl & TIOCM_RTS) > mcr |= UART_MCR_RTS; > if (mctrl & TIOCM_DTR) > @@ -440,6 +527,7 @@ static void serial_omap_break_ctl(struct uart_port *port, > int break_state) > unsigned long flags = 0; > > dev_dbg(up->port.dev, "serial_omap_break_ctl+%d\n", up->pdev->id); > + serial_omap_port_enable(up); > spin_lock_irqsave(&up->port.lock, flags); > if (break_state == -1) > up->lcr |= UART_LCR_SBC; > @@ -465,6 +553,7 @@ static int serial_omap_startup(struct uart_port *port) > > dev_dbg(up->port.dev, "serial_omap_startup+%d\n", up->pdev->id); > > + serial_omap_port_enable(up); > /* > * Clear the FIFO buffers and disable them. > * (they will be reenabled in set_termios()) > @@ -530,6 +619,8 @@ static void serial_omap_shutdown(struct uart_port *port) > unsigned long flags = 0; > > dev_dbg(up->port.dev, "serial_omap_shutdown+%d\n", up->pdev->id); > + > + serial_omap_port_enable(up); > /* > * Disable interrupts from this port > */ > @@ -668,6 +759,10 @@ serial_omap_set_termios(struct uart_port *port, struct > ktermios *termios, > baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/13); > quot = serial_omap_get_divisor(port, baud); > > + up->dll = quot & 0xff; > + up->dlh = quot >> 8; > + up->mdr1 = UART_OMAP_MDR1_DISABLE; > + > up->fcr = UART_FCR_R_TRIG_01 | UART_FCR_T_TRIG_01 | > UART_FCR_ENABLE_FIFO; > if (up->use_dma) > @@ -677,6 +772,7 @@ serial_omap_set_termios(struct uart_port *port, struct > ktermios *termios, > * Ok, we're now changing the port state. Do it with > * interrupts disabled. > */ > + serial_omap_port_enable(up); > spin_lock_irqsave(&up->port.lock, flags); > > /* > @@ -755,8 +851,11 @@ serial_omap_set_termios(struct uart_port *port, struct > ktermios *termios, > serial_out(up, UART_MCR, up->mcr); > > /* Protocol, Baud Rate, and Interrupt Settings */ > + if (up->errata & UART_ERRATA_i202_MDR1_ACCESS) > + omap_uart_mdr1_errataset(up); > + else > + serial_out(up, UART_OMAP_MDR1, up->mdr1); > > - serial_out(up, UART_OMAP_MDR1, UART_OMAP_MDR1_DISABLE); > serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); > > up->efr = serial_in(up, UART_EFR); > @@ -766,8 +865,8 @@ serial_omap_set_termios(struct uart_port *port, struct > ktermios *termios, > serial_out(up, UART_IER, 0); > serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); > > - serial_out(up, UART_DLL, quot & 0xff); /* LS of divisor */ > - serial_out(up, UART_DLM, quot >> 8); /* MS of divisor */ > + serial_out(up, UART_DLL, up->dll); /* LS of divisor */ > + serial_out(up, UART_DLM, up->dlh); /* MS of divisor */ > > serial_out(up, UART_LCR, 0); > serial_out(up, UART_IER, up->ier); > @@ -777,9 +876,14 @@ serial_omap_set_termios(struct uart_port *port, struct > ktermios *termios, > serial_out(up, UART_LCR, cval); > > if (baud > 230400 && baud != 3000000) > - serial_out(up, UART_OMAP_MDR1, UART_OMAP_MDR1_13X_MODE); > + up->mdr1 = UART_OMAP_MDR1_13X_MODE; > + else > + up->mdr1 = UART_OMAP_MDR1_16X_MODE; > + > + if (up->errata & UART_ERRATA_i202_MDR1_ACCESS) > + omap_uart_mdr1_errataset(up); > else > - serial_out(up, UART_OMAP_MDR1, UART_OMAP_MDR1_16X_MODE); > + serial_out(up, UART_OMAP_MDR1, up->mdr1); > > /* Hardware Flow Control Configuration */ > > @@ -818,6 +922,8 @@ serial_omap_pm(struct uart_port *port, unsigned int state, > unsigned char efr; > > dev_dbg(up->port.dev, "serial_omap_pm+%d\n", up->pdev->id); > + > + serial_omap_port_enable(up); > serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); > efr = serial_in(up, UART_EFR); > serial_out(up, UART_EFR, efr | UART_EFR_ECB); > @@ -827,6 +933,8 @@ serial_omap_pm(struct uart_port *port, unsigned int state, > serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); > serial_out(up, UART_EFR, efr); > serial_out(up, UART_LCR, 0); > + if (state) > + serial_omap_port_disable(up); FYI... this change doesn't apply when basing on the commit you mentioned in PATCH 0/7. > } > > static void serial_omap_release_port(struct uart_port *port) > @@ -904,6 +1012,8 @@ static inline void wait_for_xmitr(struct uart_omap_port > *up) > static void serial_omap_poll_put_char(struct uart_port *port, unsigned char > ch) > { > struct uart_omap_port *up = (struct uart_omap_port *)port; > + > + serial_omap_port_enable(up); > wait_for_xmitr(up); > serial_out(up, UART_TX, ch); > } > @@ -911,8 +1021,10 @@ static void serial_omap_poll_put_char(struct uart_port > *port, unsigned char ch) > static int serial_omap_poll_get_char(struct uart_port *port) > { > struct uart_omap_port *up = (struct uart_omap_port *)port; > - unsigned int status = serial_in(up, UART_LSR); > + unsigned int status; > > + serial_omap_port_enable(up); > + status = serial_in(up, UART_LSR); > if (!(status & UART_LSR_DR)) > return NO_POLL_CHAR; > > @@ -922,7 +1034,6 @@ static int serial_omap_poll_get_char(struct uart_port > *port) > #endif /* CONFIG_CONSOLE_POLL */ > > #ifdef CONFIG_SERIAL_OMAP_CONSOLE > - > static struct uart_omap_port *serial_omap_console_ports[4]; > > static struct uart_driver serial_omap_reg; > @@ -931,6 +1042,7 @@ static void serial_omap_console_putchar(struct uart_port > *port, int ch) > { > struct uart_omap_port *up = (struct uart_omap_port *)port; > > + serial_omap_port_enable(up); > wait_for_xmitr(up); > serial_out(up, UART_TX, ch); > } > @@ -944,6 +1056,7 @@ serial_omap_console_write(struct console *co, const char > *s, > unsigned int ier; > int locked = 1; > > + serial_omap_port_enable(up); > local_irq_save(flags); > if (up->port.sysrq) > locked = 0; > @@ -1058,22 +1171,25 @@ static struct uart_driver serial_omap_reg = { > .cons = OMAP_CONSOLE, > }; > > -static int > -serial_omap_suspend(struct platform_device *pdev, pm_message_t state) > +static int serial_omap_suspend(struct device *dev) > { > - struct uart_omap_port *up = platform_get_drvdata(pdev); > + struct uart_omap_port *up = dev_get_drvdata(dev); > > - if (up) > + if (up) { > uart_suspend_port(&serial_omap_reg, &up->port); > + serial_omap_port_disable(up); > + } > + > return 0; > } > > -static int serial_omap_resume(struct platform_device *dev) > +static int serial_omap_resume(struct device *dev) > { > - struct uart_omap_port *up = platform_get_drvdata(dev); > + struct uart_omap_port *up = dev_get_drvdata(dev); > > if (up) > uart_resume_port(&serial_omap_reg, &up->port); > + > return 0; > } > > @@ -1221,9 +1337,10 @@ static void uart_tx_dma_callback(int lch, u16 > ch_status, void *data) > > static int serial_omap_probe(struct platform_device *pdev) > { > - struct uart_omap_port *up; > + struct uart_omap_port *up = NULL; > struct resource *mem, *irq, *dma_tx, *dma_rx; > struct omap_uart_port_info *omap_up_info = pdev->dev.platform_data; > + struct omap_device *od; > int ret = -ENOSPC; > > mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); > @@ -1273,12 +1390,23 @@ static int serial_omap_probe(struct platform_device > *pdev) > up->port.ops = &serial_omap_pops; > up->port.line = pdev->id; > > - up->port.membase = omap_up_info->membase; > - up->port.mapbase = omap_up_info->mapbase; > + up->port.mapbase = mem->start; > + up->port.membase = ioremap(mem->start, mem->end - mem->start); > + > + if (!up->port.membase) { > + dev_err(&pdev->dev, "can't ioremap UART\n"); > + ret = -ENOMEM; > + goto err1; > + } > + > up->port.flags = omap_up_info->flags; > - up->port.irqflags = omap_up_info->irqflags; > up->port.uartclk = omap_up_info->uartclk; > up->uart_dma.uart_base = mem->start; > + up->errata = omap_up_info->errata; > + > + up->wk_st = omap_up_info->wk_st; > + up->wk_en = omap_up_info->wk_en; > + up->wk_mask = omap_up_info->wk_mask; > > if (omap_up_info->dma_enabled) { > up->uart_dma.uart_dma_tx = dma_tx->start; > @@ -1291,19 +1419,35 @@ static int serial_omap_probe(struct platform_device > *pdev) > up->uart_dma.tx_dma_channel = OMAP_UART_DMA_CH_FREE; > up->uart_dma.rx_dma_channel = OMAP_UART_DMA_CH_FREE; > } > + init_timer(&(up->inactivity_timer)); > + up->inactivity_timer.function = serial_omap_inactivity_timer; > + up->inactivity_timer.data = up->pdev->id; > + > + pm_runtime_enable(&pdev->dev); > + pm_runtime_irq_safe(&pdev->dev); The changelog should describe why the IRQ-safe mode is needed. > + if (omap_up_info->console_uart) { > + od = container_of(pdev, struct omap_device, pdev); > + omap_hwmod_idle(od->hwmods[0]); This was only in mach-omap2/serial.c because the early UART probing was accessing registers. With this driver becoming runtime PM aware, this hack should not be needed, and the oh->flags |= HWMOD_INIT_NO_IDLE | HWMOD_INIT_NO_RESET; should be removed from mach-omap2/serial.c > + serial_omap_port_enable(up); > + } > > ui[pdev->id] = up; > serial_omap_add_console_port(up); > > ret = uart_add_one_port(&serial_omap_reg, &up->port); > if (ret != 0) > - goto do_release_region; > + goto err1; > > + dev_set_drvdata(&pdev->dev, up); > platform_set_drvdata(pdev, up); > + > return 0; > err: > dev_err(&pdev->dev, "[UART%d]: failure [%s]: %d\n", > pdev->id, __func__, ret); > +err1: > + kfree(up); > do_release_region: > release_mem_region(mem->start, (mem->end - mem->start) + 1); > return ret; > @@ -1315,20 +1459,138 @@ static int serial_omap_remove(struct platform_device > *dev) > > platform_set_drvdata(dev, NULL); > if (up) { > + pm_runtime_disable(&up->pdev->dev); > uart_remove_one_port(&serial_omap_reg, &up->port); > kfree(up); > } > 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 omap_uart_mdr1_errataset(struct uart_omap_port *up) > +{ > + u8 timeout = 255; > + > + serial_out(up, UART_OMAP_MDR1, up->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 omap_uart_restore_context(struct uart_omap_port *up) > +{ > + u16 efr = 0; > + > + if (up->errata & UART_ERRATA_i202_MDR1_ACCESS) > + omap_uart_mdr1_errataset(up); > + else > + serial_out(up, UART_OMAP_MDR1, up->mdr1); > + serial_out(up, UART_LCR, 0xBF); /* Config B mode */ > + efr = serial_in(up, UART_EFR); > + serial_out(up, UART_EFR, UART_EFR_ECB); > + serial_out(up, UART_LCR, 0x0); /* Operational mode */ > + serial_out(up, UART_IER, 0x0); > + serial_out(up, UART_LCR, 0xBF); /* Config B mode */ > + serial_out(up, UART_DLL, up->dll); > + serial_out(up, UART_DLM, up->dlh); > + serial_out(up, UART_LCR, 0x0); /* Operational mode */ > + serial_out(up, UART_IER, up->ier); > + serial_out(up, UART_FCR, up->fcr); > + serial_out(up, UART_LCR, 0x80); > + serial_out(up, UART_MCR, up->mcr); > + serial_out(up, UART_LCR, 0xBF); /* Config B mode */ > + serial_out(up, UART_EFR, efr); > + serial_out(up, UART_LCR, UART_LCR_WLEN8); > + if (up->errata & UART_ERRATA_i202_MDR1_ACCESS) > + omap_uart_mdr1_errataset(up); > + else > + /* UART 16x mode */ > + serial_out(up, UART_OMAP_MDR1, up->mdr1); > +} > + > +static void omap_uart_enable_wakeup(struct uart_omap_port *up) > +{ > + /* Set wake-enable bit */ > + if (up->wk_en && up->wk_mask) { > + u32 v = __raw_readl(up->wk_en); > + v |= up->wk_mask; > + __raw_writel(v, up->wk_en); > + } > +} > + > +static void omap_uart_disable_wakeup(struct uart_omap_port *up) > +{ > + /* Clear wake-enable bit */ > + if (up->wk_en && up->wk_mask) { > + u32 v = __raw_readl(up->wk_en); > + v &= ~up->wk_mask; > + __raw_writel(v, up->wk_en); > + } > +} Again, driver should not be doing direct PRCM accesses here. For now, how about leaving these also in mach-omap2/serial.c and calling them via pdata function pointers: if (pdata->enable_wakeup) pdata->enable_wakeup() > +static int omap_serial_runtime_suspend(struct device *dev) > +{ > + struct uart_omap_port *up = dev_get_drvdata(dev); > + > + if (!up) > + goto done; > + > + if (device_may_wakeup(&up->pdev->dev)) > + omap_uart_enable_wakeup(up); > + else > + omap_uart_disable_wakeup(up); > +done: > + return 0; > +} > + > +static int omap_serial_runtime_resume(struct device *dev) > +{ > + struct uart_omap_port *up = dev_get_drvdata(dev); > + > + if (!up) > + goto done; > + > + omap_uart_restore_context(up); > +done: > + return 0; > +} > + > +static const struct dev_pm_ops omap_serial_dev_pm_ops = { > + .suspend = serial_omap_suspend, > + .resume = serial_omap_resume, > + .runtime_suspend = omap_serial_runtime_suspend, > + .runtime_resume = omap_serial_runtime_resume, > +}; > + > static struct platform_driver serial_omap_driver = { > .probe = serial_omap_probe, > .remove = serial_omap_remove, > - > - .suspend = serial_omap_suspend, > - .resume = serial_omap_resume, > .driver = { > .name = DRIVER_NAME, > + .pm = &omap_serial_dev_pm_ops, > }, > }; Kevin -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
