| Message ID | 1456501724-28477-7-git-send-email-jonathanh@nvidia.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
On Fri, Feb 26, 2016 at 03:48:40PM +0000, Jon Hunter wrote: > Currently, the function tegra_powergate_set() simply sets the desired > powergate state but does not wait for the state to change. In most cases > we should wait for the state to change before proceeding. Currently, there > is a case for tegra114 and tegra124 devices where we do not wait when > starting the secondary CPU as this is not necessary. However, this is only > done at boot time and so waiting here will only have a small impact on > boot time. Therefore, update tegra_powergate_set() to wait when setting > the powergate. > > By adding this feature, we can also eliminate the polling loop from > tegra30_boot_secondary(). > > A function has been added for checking the status of the powergate and > so update the tegra_powergate_is_powered() to use this macro as well. > > Signed-off-by: Jon Hunter <jonathanh@nvidia.com> > --- > arch/arm/mach-tegra/platsmp.c | 16 +++------------- > drivers/soc/tegra/pmc.c | 9 ++++++++- > 2 files changed, 11 insertions(+), 14 deletions(-) This looks to be independent from the generic power domain support. Can I apply this separately (for 4.6, without waiting for the power domain series' dependencies to go in)? Thierry
On 29/02/16 07:24, Thierry Reding wrote: > * PGP Signed by an unknown key > > On Fri, Feb 26, 2016 at 03:48:40PM +0000, Jon Hunter wrote: >> Currently, the function tegra_powergate_set() simply sets the desired >> powergate state but does not wait for the state to change. In most cases >> we should wait for the state to change before proceeding. Currently, there >> is a case for tegra114 and tegra124 devices where we do not wait when >> starting the secondary CPU as this is not necessary. However, this is only >> done at boot time and so waiting here will only have a small impact on >> boot time. Therefore, update tegra_powergate_set() to wait when setting >> the powergate. >> >> By adding this feature, we can also eliminate the polling loop from >> tegra30_boot_secondary(). >> >> A function has been added for checking the status of the powergate and >> so update the tegra_powergate_is_powered() to use this macro as well. >> >> Signed-off-by: Jon Hunter <jonathanh@nvidia.com> >> --- >> arch/arm/mach-tegra/platsmp.c | 16 +++------------- >> drivers/soc/tegra/pmc.c | 9 ++++++++- >> 2 files changed, 11 insertions(+), 14 deletions(-) > > This looks to be independent from the generic power domain support. Can > I apply this separately (for 4.6, without waiting for the power domain > series' dependencies to go in)? Yes this could be applied independently of this series for v4.6. I just wanted to make sure that this change is added before the genpd changes are applied. Cheers Jon -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Fri, Feb 26, 2016 at 03:48:40PM +0000, Jon Hunter wrote: > Currently, the function tegra_powergate_set() simply sets the desired > powergate state but does not wait for the state to change. In most cases > we should wait for the state to change before proceeding. Currently, there > is a case for tegra114 and tegra124 devices where we do not wait when > starting the secondary CPU as this is not necessary. However, this is only > done at boot time and so waiting here will only have a small impact on > boot time. Therefore, update tegra_powergate_set() to wait when setting > the powergate. > > By adding this feature, we can also eliminate the polling loop from > tegra30_boot_secondary(). > > A function has been added for checking the status of the powergate and > so update the tegra_powergate_is_powered() to use this macro as well. > > Signed-off-by: Jon Hunter <jonathanh@nvidia.com> > --- > arch/arm/mach-tegra/platsmp.c | 16 +++------------- > drivers/soc/tegra/pmc.c | 9 ++++++++- > 2 files changed, 11 insertions(+), 14 deletions(-) Applied, thanks. Thierry
diff --git a/arch/arm/mach-tegra/platsmp.c b/arch/arm/mach-tegra/platsmp.c index f3f61dbbda97..75620ae73913 100644 --- a/arch/arm/mach-tegra/platsmp.c +++ b/arch/arm/mach-tegra/platsmp.c @@ -108,19 +108,9 @@ static int tegra30_boot_secondary(unsigned int cpu, struct task_struct *idle) * be un-gated by un-toggling the power gate register * manually. */ - if (!tegra_pmc_cpu_is_powered(cpu)) { - ret = tegra_pmc_cpu_power_on(cpu); - if (ret) - return ret; - - /* Wait for the power to come up. */ - timeout = jiffies + msecs_to_jiffies(100); - while (!tegra_pmc_cpu_is_powered(cpu)) { - if (time_after(jiffies, timeout)) - return -ETIMEDOUT; - udelay(10); - } - } + ret = tegra_pmc_cpu_power_on(cpu); + if (ret) + return ret; remove_clamps: /* CPU partition is powered. Enable the CPU clock. */ diff --git a/drivers/soc/tegra/pmc.c b/drivers/soc/tegra/pmc.c index e4fd40fa27e8..08966c26d65c 100644 --- a/drivers/soc/tegra/pmc.c +++ b/drivers/soc/tegra/pmc.c @@ -28,6 +28,7 @@ #include <linux/export.h> #include <linux/init.h> #include <linux/io.h> +#include <linux/iopoll.h> #include <linux/of.h> #include <linux/of_address.h> #include <linux/platform_device.h> @@ -194,6 +195,9 @@ static inline bool tegra_powergate_is_valid(int id) */ static int tegra_powergate_set(unsigned int id, bool new_state) { + bool status; + int err; + if (id == TEGRA_POWERGATE_3D && pmc->soc->has_gpu_clamps) return -EINVAL; @@ -206,9 +210,12 @@ static int tegra_powergate_set(unsigned int id, bool new_state) tegra_pmc_writel(PWRGATE_TOGGLE_START | id, PWRGATE_TOGGLE); + err = readx_poll_timeout(tegra_powergate_state, id, status, + status == new_state, 10, 100000); + mutex_unlock(&pmc->powergates_lock); - return 0; + return err; } /**
Currently, the function tegra_powergate_set() simply sets the desired powergate state but does not wait for the state to change. In most cases we should wait for the state to change before proceeding. Currently, there is a case for tegra114 and tegra124 devices where we do not wait when starting the secondary CPU as this is not necessary. However, this is only done at boot time and so waiting here will only have a small impact on boot time. Therefore, update tegra_powergate_set() to wait when setting the powergate. By adding this feature, we can also eliminate the polling loop from tegra30_boot_secondary(). A function has been added for checking the status of the powergate and so update the tegra_powergate_is_powered() to use this macro as well. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> --- arch/arm/mach-tegra/platsmp.c | 16 +++------------- drivers/soc/tegra/pmc.c | 9 ++++++++- 2 files changed, 11 insertions(+), 14 deletions(-)