Hi
a few comments:
On Tue, 4 Oct 2011, Vishwanath BS wrote:
> As per OMAP3630 TRM Section 3.5.7.2.2, the right sequence for enabling IO Daisy
> chain is "The I/O wake-up scheme is enabled by triggering the I/O daisy chain
> control (Wu clock) by programming a dedicated register
> (PRCM.PM_WKEN_WKUP[16] EN_IO_CHAIN) in the PRCM module.Software must wait for
> the I/O daisy chain to complete before it transitions the PER domain to a
> nonfunctional state. This is done by polling a dedicated status bit in the PRCM
> module (PRCM.PM_WKST_WKUP[16] ST_IO_CHAIN). This status bit must be cleared by
> software when the bit is read to 1".
>
> The original code was polling on a wrong register which is fixed in this patch.
> Also omap3_enable_io_chain is made non static as it's going to be used in
> subsequent patches.
This patch should be split into a fix (for the WKEN/WKST bug) and then a
new patch that drops the 'static'. The new patch should also move this
function to prm2xxx_3xxx.c for the same reason that the OMAP4 version of
this function should be in prminst44xx.c.
In the medium-term, a bunch of the functions from prm2xxx_3xxx.c,
prminst44xx.c, etc. that are only used by the mach-omap2/pm*.c code should
be moved into the PRM driver that Tero is working on that will live in
drivers/.
>
> Signed-off-by: Vishwanath BS <vishwanath.bs@xxxxxx>
> ---
> arch/arm/mach-omap2/pm.h | 1 +
> arch/arm/mach-omap2/pm34xx.c | 6 +++---
> 2 files changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/arch/arm/mach-omap2/pm.h b/arch/arm/mach-omap2/pm.h
> index 4e166ad..9a36a7c 100644
> --- a/arch/arm/mach-omap2/pm.h
> +++ b/arch/arm/mach-omap2/pm.h
> @@ -21,6 +21,7 @@ extern void omap_sram_idle(void);
> extern int omap3_can_sleep(void);
> extern int omap_set_pwrdm_state(struct powerdomain *pwrdm, u32 state);
> extern int omap3_idle_init(void);
> +extern void omap3_enable_io_chain(void);
>
> #if defined(CONFIG_PM_OPP)
> extern int omap3_opp_init(void);
> diff --git a/arch/arm/mach-omap2/pm34xx.c b/arch/arm/mach-omap2/pm34xx.c
> index 7255d9b..61f1a5b 100644
> --- a/arch/arm/mach-omap2/pm34xx.c
> +++ b/arch/arm/mach-omap2/pm34xx.c
> @@ -95,7 +95,7 @@ static inline void omap3_per_restore_context(void)
> omap_gpio_restore_context();
> }
>
> -static void omap3_enable_io_chain(void)
> +void omap3_enable_io_chain(void)
> {
> int timeout = 0;
>
> @@ -105,7 +105,7 @@ static void omap3_enable_io_chain(void)
> /* Do a readback to assure write has been done */
> omap2_prm_read_mod_reg(WKUP_MOD, PM_WKEN);
>
> - while (!(omap2_prm_read_mod_reg(WKUP_MOD, PM_WKEN) &
> + while (!(omap2_prm_read_mod_reg(WKUP_MOD, PM_WKST) &
> OMAP3430_ST_IO_CHAIN_MASK)) {
> timeout++;
> if (timeout > 1000) {
> @@ -114,7 +114,7 @@ static void omap3_enable_io_chain(void)
> return;
> }
> omap2_prm_set_mod_reg_bits(OMAP3430_ST_IO_CHAIN_MASK,
> - WKUP_MOD, PM_WKEN);
> + WKUP_MOD, PM_WKST);
> }
> }
> }
> --
> 1.7.0.4
>
> --
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>
- Paul
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