| Message ID | 1304080796-625-13-git-send-email-govindraj.raja@ti.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
"Govindraj.R" <govindraj.raja@ti.com> writes: > For omap2 cpu_idle thread will not be available Why not? > and uart_clock cutting happens only in suspend path. Aren't clocks also cut after runtime PM autosuspend? > Prior to this patch the uart_clock was cut using prepare/resume > calls since these funcs are no more available with runtime > changes use no_async_wake flag to keep clock active during bootup > otherwise uart port will disabled during boot-up and cannot be > enabled back. This doesn't just keep clock active during bootup, but it keeps clock active always, except during suspend. > Also based on this flag we can disable uart port during suspend > and enable back during resume. I think disabling UART port during suspend should already be part of an earlier patch. This patch should then only make it conditional. > Signed-off-by: Govindraj.R <govindraj.raja@ti.com> > --- > arch/arm/mach-omap2/serial.c | 7 +++++++ > arch/arm/plat-omap/include/plat/omap-serial.h | 3 +++ > drivers/tty/serial/omap-serial.c | 14 ++++++++++++++ > 3 files changed, 24 insertions(+), 0 deletions(-) > > diff --git a/arch/arm/mach-omap2/serial.c b/arch/arm/mach-omap2/serial.c > index d4ef370..1af9fd5 100644 > --- a/arch/arm/mach-omap2/serial.c > +++ b/arch/arm/mach-omap2/serial.c > @@ -245,6 +245,12 @@ static void omap_uart_wakeup_enable(struct platform_device *pdev, bool enable) > static void omap_uart_idle_init(struct omap_uart_port_info *uart, > unsigned short num) > { > + /* On omap2 no cpu_idle and async wakeup from prcm_module. Please remove comments about CPU idle, as the need for this has nothing to do with CPU idle. > + * This flag can be used to cut clocks only in suspend path. > + * to avoid boot break due to aggressive clock cutting from > + * omap-serial driver. > + */ fix multi-line comment style throughout > + uart->no_async_wake = true; If needed (which I still don't think I understand), for readability sake this flag should be called 'has_async_wake', and default to false. It should then be set to true on available SoCs. Kevin > if (cpu_is_omap34xx()) { > u32 mod = num > 1 ? OMAP3430_PER_MOD : CORE_MOD; > u32 wk_mask = 0; > @@ -266,6 +272,7 @@ static void omap_uart_idle_init(struct omap_uart_port_info *uart, > break; > } > uart->wk_mask = wk_mask; > + uart->no_async_wake = false; > } else if (cpu_is_omap24xx()) { > u32 wk_mask = 0; > u32 wk_en = PM_WKEN1, wk_st = PM_WKST1; > diff --git a/arch/arm/plat-omap/include/plat/omap-serial.h b/arch/arm/plat-omap/include/plat/omap-serial.h > index b5117bd..1de5bc4 100644 > --- a/arch/arm/plat-omap/include/plat/omap-serial.h > +++ b/arch/arm/plat-omap/include/plat/omap-serial.h > @@ -79,6 +79,7 @@ struct omap_uart_port_info { > void __iomem *wk_st; > void __iomem *wk_en; > u32 wk_mask; > + bool no_async_wake; > }; > > struct uart_omap_dma { > @@ -134,6 +135,8 @@ struct uart_omap_port { > unsigned int errata; > void (*enable_wakeup)(struct platform_device *, bool); > bool (*chk_wakeup)(struct platform_device *); > + > + bool no_async_wake; > }; > > #endif /* __OMAP_SERIAL_H__ */ > diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c > index eea478c..59f548f 100644 > --- a/drivers/tty/serial/omap-serial.c > +++ b/drivers/tty/serial/omap-serial.c > @@ -1168,6 +1168,13 @@ static int serial_omap_suspend(struct device *dev) > uart_suspend_port(&serial_omap_reg, &up->port); > console_trylock(); > serial_omap_pm(&up->port, 3, 0); > + > + /* OMAP2 dont have cpu_idle thread and async wakeup from prcm. > + * For such socs clocks will be kept active from probe and > + * cut only in suspend path. > + */ > + if (up->no_async_wake) > + serial_omap_port_disable(up); > } > return 0; > } > @@ -1179,6 +1186,9 @@ static int serial_omap_resume(struct device *dev) > if (up) { > uart_resume_port(&serial_omap_reg, &up->port); > console_unlock(); > + > + if (up->no_async_wake) > + serial_omap_port_enable(up); > } > > return 0; > @@ -1402,6 +1412,7 @@ static int serial_omap_probe(struct platform_device *pdev) > up->errata = omap_up_info->errata; > up->enable_wakeup = omap_up_info->enable_wakeup; > up->chk_wakeup = omap_up_info->chk_wakeup; > + up->no_async_wake = omap_up_info->no_async_wake; > > if (omap_up_info->dma_enabled) { > up->uart_dma.uart_dma_tx = dma_tx->start; > @@ -1430,6 +1441,9 @@ static int serial_omap_probe(struct platform_device *pdev) > serial_omap_port_disable(up); > } > > + if (up->no_async_wake) > + serial_omap_port_enable(up); > + > ui[pdev->id] = up; > serial_omap_add_console_port(up); -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/arm/mach-omap2/serial.c b/arch/arm/mach-omap2/serial.c index d4ef370..1af9fd5 100644 --- a/arch/arm/mach-omap2/serial.c +++ b/arch/arm/mach-omap2/serial.c @@ -245,6 +245,12 @@ static void omap_uart_wakeup_enable(struct platform_device *pdev, bool enable) static void omap_uart_idle_init(struct omap_uart_port_info *uart, unsigned short num) { + /* On omap2 no cpu_idle and async wakeup from prcm_module. + * This flag can be used to cut clocks only in suspend path. + * to avoid boot break due to aggressive clock cutting from + * omap-serial driver. + */ + uart->no_async_wake = true; if (cpu_is_omap34xx()) { u32 mod = num > 1 ? OMAP3430_PER_MOD : CORE_MOD; u32 wk_mask = 0; @@ -266,6 +272,7 @@ static void omap_uart_idle_init(struct omap_uart_port_info *uart, break; } uart->wk_mask = wk_mask; + uart->no_async_wake = false; } else if (cpu_is_omap24xx()) { u32 wk_mask = 0; u32 wk_en = PM_WKEN1, wk_st = PM_WKST1; diff --git a/arch/arm/plat-omap/include/plat/omap-serial.h b/arch/arm/plat-omap/include/plat/omap-serial.h index b5117bd..1de5bc4 100644 --- a/arch/arm/plat-omap/include/plat/omap-serial.h +++ b/arch/arm/plat-omap/include/plat/omap-serial.h @@ -79,6 +79,7 @@ struct omap_uart_port_info { void __iomem *wk_st; void __iomem *wk_en; u32 wk_mask; + bool no_async_wake; }; struct uart_omap_dma { @@ -134,6 +135,8 @@ struct uart_omap_port { unsigned int errata; void (*enable_wakeup)(struct platform_device *, bool); bool (*chk_wakeup)(struct platform_device *); + + bool no_async_wake; }; #endif /* __OMAP_SERIAL_H__ */ diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c index eea478c..59f548f 100644 --- a/drivers/tty/serial/omap-serial.c +++ b/drivers/tty/serial/omap-serial.c @@ -1168,6 +1168,13 @@ static int serial_omap_suspend(struct device *dev) uart_suspend_port(&serial_omap_reg, &up->port); console_trylock(); serial_omap_pm(&up->port, 3, 0); + + /* OMAP2 dont have cpu_idle thread and async wakeup from prcm. + * For such socs clocks will be kept active from probe and + * cut only in suspend path. + */ + if (up->no_async_wake) + serial_omap_port_disable(up); } return 0; } @@ -1179,6 +1186,9 @@ static int serial_omap_resume(struct device *dev) if (up) { uart_resume_port(&serial_omap_reg, &up->port); console_unlock(); + + if (up->no_async_wake) + serial_omap_port_enable(up); } return 0; @@ -1402,6 +1412,7 @@ static int serial_omap_probe(struct platform_device *pdev) up->errata = omap_up_info->errata; up->enable_wakeup = omap_up_info->enable_wakeup; up->chk_wakeup = omap_up_info->chk_wakeup; + up->no_async_wake = omap_up_info->no_async_wake; if (omap_up_info->dma_enabled) { up->uart_dma.uart_dma_tx = dma_tx->start; @@ -1430,6 +1441,9 @@ static int serial_omap_probe(struct platform_device *pdev) serial_omap_port_disable(up); } + if (up->no_async_wake) + serial_omap_port_enable(up); + ui[pdev->id] = up; serial_omap_add_console_port(up);
For omap2 cpu_idle thread will not be available and uart_clock cutting happens only in suspend path. Prior to this patch the uart_clock was cut using prepare/resume calls since these funcs are no more available with runtime changes use no_async_wake flag to keep clock active during bootup otherwise uart port will disabled during boot-up and cannot be enabled back. Also based on this flag we can disable uart port during suspend and enable back during resume. Signed-off-by: Govindraj.R <govindraj.raja@ti.com> --- arch/arm/mach-omap2/serial.c | 7 +++++++ arch/arm/plat-omap/include/plat/omap-serial.h | 3 +++ drivers/tty/serial/omap-serial.c | 14 ++++++++++++++ 3 files changed, 24 insertions(+), 0 deletions(-)