| Message ID | 20200909200930.232174-3-seanga2@gmail.com |
|---|---|
| State | Superseded |
| Delegated to: | Andes |
| Headers | show |
| Series | riscv: Clean up timer drivers | expand |
On Wed, 9 Sep 2020 at 14:09, Sean Anderson <seanga2@gmail.com> wrote: > > This function is designed to be used when a timer used to be initialized by > the cpu (e.g. RISC-V timers), but now is initialized by dm_timer_init. In > such a case, the timer may prefer to use the clocks and clock-frequency > properties, but should be able to fall back on using the cpu's > timebase-frequency. > > Signed-off-by: Sean Anderson <seanga2@gmail.com> > --- > > Changes in v4: > - New > > drivers/timer/timer-uclass.c | 25 +++++++++++++++++++++++++ > include/timer.h | 15 +++++++++++++++ > 2 files changed, 40 insertions(+) > Reviewed-by: Simon Glass <sjg@chromium.org> Can this be tested with sandbox?
On 9/10/20 9:38 AM, Simon Glass wrote: > On Wed, 9 Sep 2020 at 14:09, Sean Anderson <seanga2@gmail.com> wrote: >> >> This function is designed to be used when a timer used to be initialized by >> the cpu (e.g. RISC-V timers), but now is initialized by dm_timer_init. In >> such a case, the timer may prefer to use the clocks and clock-frequency >> properties, but should be able to fall back on using the cpu's >> timebase-frequency. >> >> Signed-off-by: Sean Anderson <seanga2@gmail.com> >> --- >> >> Changes in v4: >> - New >> >> drivers/timer/timer-uclass.c | 25 +++++++++++++++++++++++++ >> include/timer.h | 15 +++++++++++++++ >> 2 files changed, 40 insertions(+) >> > > Reviewed-by: Simon Glass <sjg@chromium.org> > > Can this be tested with sandbox? > Probably. I can add a test in the next revision. --Sean
On Thu, Sep 10, 2020 at 4:09 AM Sean Anderson <seanga2@gmail.com> wrote: > > This function is designed to be used when a timer used to be initialized by > the cpu (e.g. RISC-V timers), but now is initialized by dm_timer_init. In > such a case, the timer may prefer to use the clocks and clock-frequency > properties, but should be able to fall back on using the cpu's > timebase-frequency. > > Signed-off-by: Sean Anderson <seanga2@gmail.com> > --- > > Changes in v4: > - New > > drivers/timer/timer-uclass.c | 25 +++++++++++++++++++++++++ > include/timer.h | 15 +++++++++++++++ > 2 files changed, 40 insertions(+) > Reviewed-by: Bin Meng <bin.meng@windriver.com>
diff --git a/drivers/timer/timer-uclass.c b/drivers/timer/timer-uclass.c index 14dde950a1..fb2f4c351a 100644 --- a/drivers/timer/timer-uclass.c +++ b/drivers/timer/timer-uclass.c @@ -4,6 +4,7 @@ */ #include <common.h> +#include <cpu.h> #include <dm.h> #include <init.h> #include <dm/lists.h> @@ -79,6 +80,30 @@ static int timer_post_probe(struct udevice *dev) return 0; } +int timer_timebase_fallback(struct udevice *dev) +{ + struct udevice *cpu; + struct cpu_platdata *cpu_plat; + struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev); + + /* Did we get our clock rate from the device tree? */ + if (uc_priv->clock_rate) + return 0; + + /* Fall back to timebase-frequency */ + dev_dbg(dev, "missing clocks or clock-frequency property; falling back on timebase-frequency\n"); + cpu = cpu_get_current_dev(); + if (!cpu) + return -ENODEV; + + cpu_plat = dev_get_parent_platdata(cpu); + if (!cpu_plat) + return -ENODEV; + + uc_priv->clock_rate = cpu_plat->timebase_freq; + return 0; +} + u64 timer_conv_64(u32 count) { /* increment tbh if tbl has rolled over */ diff --git a/include/timer.h b/include/timer.h index a49b500ce3..8b9fa51c53 100644 --- a/include/timer.h +++ b/include/timer.h @@ -15,6 +15,21 @@ */ int dm_timer_init(void); +/** + * timer_timebase_fallback() - Helper for timers using timebase fallback + * @dev: A timer partially-probed timer device + * + * This is a helper function designed for timers which need to fall back on the + * cpu's timebase. This function is designed to be called during the driver's + * probe(). If there is a clocks or clock-frequency property in the timer's + * binding, then it will be used. Otherwise, the timebase of the current cpu + * will be used. This is initialized by the cpu driver, and usually gotten from + * ``/cpus/timebase-frequency`` or ``/cpus/cpu@X/timebase-frequency``. + * + * Return: 0 if OK, or negative error code on failure + */ +int timer_timebase_fallback(struct udevice *dev); + /* * timer_conv_64 - convert 32-bit counter value to 64-bit *
This function is designed to be used when a timer used to be initialized by the cpu (e.g. RISC-V timers), but now is initialized by dm_timer_init. In such a case, the timer may prefer to use the clocks and clock-frequency properties, but should be able to fall back on using the cpu's timebase-frequency. Signed-off-by: Sean Anderson <seanga2@gmail.com> --- Changes in v4: - New drivers/timer/timer-uclass.c | 25 +++++++++++++++++++++++++ include/timer.h | 15 +++++++++++++++ 2 files changed, 40 insertions(+)