Hi Tero,
On 04/20/2012 04:33 AM, Tero Kristo wrote:
> From: Santosh Shilimkar <santosh.shilimkar@xxxxxx>
>
> The ROM BUG is when MPU Domain OFF wake up sequence that can compromise
> IVA and Tesla execution.
>
> At wakeup from MPU OFF on HS device only (not GP device), when
> restoring the Secure RAM, the ROM Code reconfigures the clocks the
> same way it is done at Cold Reset.
> The IVAHD Clocks and Power Domain settings are:
> IVAHD_CM2 IVAHD_CLKCTRL_MODULE_MODE = DISABLE
> IVAHD_CM2 SL2_CLKCTRL_MODULE_MODE = DISABLE
> IVAHD_CM2 SL2_CLKSTCTRL_CLKTRCTRL = HW_AUTO
> IVAHD_PRM IVAHD_PWRSTCTRL_POWERSTATE = OFF
> The TESLA Clocks and Power Domain settings are:
> TESLA_CM1 TESLA_CLKCTRL_MODULE_MODE = DISABLE
> TESLA_CM1 TESLA_CLKSTCTRL_CLKTRCTRL = HW_AUTO
> TESLA_PRM TESLA_PWRSTCTRL_POWERSTATE = OFF
>
> This patch fixes the low power OFF mode code so that the these
> registers are saved and restore across MPU OFF state.
>
> Also because of this limitation, MPU OFF alone is not targeted without
> device OFF to avoid IVAHD and TESLA execution impact
You may wish to state which devices is impacted by this in the changelog.
> Signed-off-by: Rajendra Nayak <rnayak@xxxxxx>
> Signed-off-by: Santosh Shilimkar <santosh.shilimkar@xxxxxx>
> [t-kristo@xxxxxx: added omap4 pm errata support]
> Signed-off-by: Tero Kristo <t-kristo@xxxxxx>
> ---
> arch/arm/mach-omap2/omap-mpuss-lowpower.c | 53 +++++++++++++++++++++++++++++
> arch/arm/mach-omap2/pm.h | 2 +
> arch/arm/mach-omap2/pm44xx.c | 9 +++++
> 3 files changed, 64 insertions(+), 0 deletions(-)
>
> diff --git a/arch/arm/mach-omap2/omap-mpuss-lowpower.c b/arch/arm/mach-omap2/omap-mpuss-lowpower.c
> index b9a2cc7..208d4a4 100644
> --- a/arch/arm/mach-omap2/omap-mpuss-lowpower.c
> +++ b/arch/arm/mach-omap2/omap-mpuss-lowpower.c
> @@ -52,6 +52,7 @@
>
> #include <plat/omap44xx.h>
>
> +#include "iomap.h"
> #include "common.h"
> #include "omap4-sar-layout.h"
> #include "pm.h"
> @@ -76,6 +77,24 @@ static DEFINE_PER_CPU(struct omap4_cpu_pm_info, omap4_pm_info);
> static struct powerdomain *mpuss_pd;
> static void __iomem *sar_base;
>
> +struct reg_tuple {
> + void __iomem *addr;
> + u32 val;
> +};
> +
> +static struct reg_tuple tesla_reg[] = {
> + {.addr = OMAP4430_CM_TESLA_CLKSTCTRL},
> + {.addr = OMAP4430_CM_TESLA_TESLA_CLKCTRL},
> + {.addr = OMAP4430_PM_TESLA_PWRSTCTRL},
> +};
> +
> +static struct reg_tuple ivahd_reg[] = {
> + {.addr = OMAP4430_CM_IVAHD_CLKSTCTRL},
> + {.addr = OMAP4430_CM_IVAHD_IVAHD_CLKCTRL},
> + {.addr = OMAP4430_CM_IVAHD_SL2_CLKCTRL},
> + {.addr = OMAP4430_PM_IVAHD_PWRSTCTRL}
> +};
> +
> /*
> * Program the wakeup routine address for the CPU0 and CPU1
> * used for OFF or DORMANT wakeup.
> @@ -215,6 +234,34 @@ static void save_l2x0_context(void)
> {}
> #endif
>
> +static inline void save_ivahd_tesla_regs(void)
> +{
> + int i;
> +
> + if (!IS_PM44XX_ERRATUM(PM_OMAP4_ROM_IVAHD_TESLA_ERRATUM))
> + return;
> +
> + for (i = 0; i < ARRAY_SIZE(tesla_reg); i++)
> + tesla_reg[i].val = __raw_readl(tesla_reg[i].addr);
> +
> + for (i = 0; i < ARRAY_SIZE(ivahd_reg); i++)
> + ivahd_reg[i].val = __raw_readl(ivahd_reg[i].addr);
> +}
> +
> +static inline void restore_ivahd_tesla_regs(void)
> +{
> + int i;
> +
> + if (!IS_PM44XX_ERRATUM(PM_OMAP4_ROM_IVAHD_TESLA_ERRATUM))
> + return;
> +
> + for (i = 0; i < ARRAY_SIZE(tesla_reg); i++)
> + __raw_writel(tesla_reg[i].val, tesla_reg[i].addr);
> +
> + for (i = 0; i < ARRAY_SIZE(ivahd_reg); i++)
> + __raw_writel(ivahd_reg[i].val, ivahd_reg[i].addr);
> +}
> +
> /**
> * omap4_enter_lowpower: OMAP4 MPUSS Low Power Entry Function
> * The purpose of this function is to manage low power programming
> @@ -273,11 +320,14 @@ int omap4_enter_lowpower(unsigned int cpu, unsigned int power_state)
> omap_sar_overwrite();
> omap4_cm_prepare_off();
> omap4_dpll_prepare_off();
> + save_ivahd_tesla_regs();
> save_state = 3;
> } else if ((pwrdm_read_next_pwrst(mpuss_pd) == PWRDM_POWER_RET) &&
> (pwrdm_read_logic_retst(mpuss_pd) == PWRDM_POWER_OFF)) {
> + save_ivahd_tesla_regs();
> save_state = 2;
> } else if (pwrdm_read_next_pwrst(mpuss_pd) == PWRDM_POWER_OFF) {
> + save_ivahd_tesla_regs();
> save_state = 3;
> }
>
> @@ -302,6 +352,9 @@ int omap4_enter_lowpower(unsigned int cpu, unsigned int power_state)
> wakeup_cpu = smp_processor_id();
> set_cpu_next_pwrst(wakeup_cpu, PWRDM_POWER_ON);
>
> + if (omap4_mpuss_read_prev_context_state())
> + restore_ivahd_tesla_regs();
> +
> if (omap4_device_prev_state_off()) {
> omap4_dpll_resume_off();
> omap4_cm_resume_off();
> diff --git a/arch/arm/mach-omap2/pm.h b/arch/arm/mach-omap2/pm.h
> index e78ec63..051aeb9 100644
> --- a/arch/arm/mach-omap2/pm.h
> +++ b/arch/arm/mach-omap2/pm.h
> @@ -131,6 +131,8 @@ extern void enable_omap3630_toggle_l2_on_restore(void);
> static inline void enable_omap3630_toggle_l2_on_restore(void) { }
> #endif /* defined(CONFIG_PM) && defined(CONFIG_ARCH_OMAP3) */
>
> +#define PM_OMAP4_ROM_IVAHD_TESLA_ERRATUM (1 << 0)
> +
> #if defined(CONFIG_PM) && defined(CONFIG_ARCH_OMAP4)
> extern u16 pm44xx_errata;
> #define IS_PM44XX_ERRATUM(id) (pm44xx_errata & (id))
> diff --git a/arch/arm/mach-omap2/pm44xx.c b/arch/arm/mach-omap2/pm44xx.c
> index 8238097..67cb799 100644
> --- a/arch/arm/mach-omap2/pm44xx.c
> +++ b/arch/arm/mach-omap2/pm44xx.c
> @@ -263,6 +263,15 @@ static int __init omap4_pm_init(void)
>
> (void) clkdm_for_each(omap_pm_clkdms_setup, NULL);
>
> + /*
> + * ROM code initializes IVAHD and TESLA clock registers during
> + * secure RAM restore phase on omap4430 EMU/HS devices, thus
> + * IVAHD / TESLA clock registers must be saved / restored
> + * during MPU OSWR / device off.
> + */
> + if (cpu_is_omap443x() && omap_type() != OMAP2_DEVICE_TYPE_GP)
> + pm44xx_errata |= PM_OMAP4_ROM_IVAHD_TESLA_ERRATUM;
This erratum does not impact omap4430 es2.3 so the above should account
for that.
Cheers
Jon
--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
