Add support to the Tegra CPU reset vector to detect whether the CPU is resuming from LP1 suspend state. If it is, branch to the LP1-specific resume code. When Tegra enters the LP1 suspend state, the SDRAM controller is placed into a self-refresh state. For this reason, we must place the LP1 resume code into IRAM, so that it is accessible before SDRAM access has been re-enabled. Signed-off-by: Joseph Lo <josephl@xxxxxxxxxx> --- V2: * update the commit message * move the define of IRAM_CODE_AREA to iomap.h * move the THUMB marco code before the 'bx' instruction --- arch/arm/mach-tegra/iomap.h | 2 ++ arch/arm/mach-tegra/reset-handler.S | 13 +++++++++++++ arch/arm/mach-tegra/reset.c | 2 ++ 3 files changed, 17 insertions(+) diff --git a/arch/arm/mach-tegra/iomap.h b/arch/arm/mach-tegra/iomap.h index 399fbca..f2bdcb4 100644 --- a/arch/arm/mach-tegra/iomap.h +++ b/arch/arm/mach-tegra/iomap.h @@ -24,6 +24,8 @@ #define TEGRA_IRAM_BASE 0x40000000 #define TEGRA_IRAM_SIZE SZ_256K +#define TEGRA_IRAM_CODE_AREA (TEGRA_IRAM_BASE + SZ_4K) + #define TEGRA_HOST1X_BASE 0x50000000 #define TEGRA_HOST1X_SIZE 0x24000 diff --git a/arch/arm/mach-tegra/reset-handler.S b/arch/arm/mach-tegra/reset-handler.S index 34614bd..f527b2c 100644 --- a/arch/arm/mach-tegra/reset-handler.S +++ b/arch/arm/mach-tegra/reset-handler.S @@ -182,6 +182,19 @@ after_errata: 1: #endif + /* Waking up from LP1? */ + ldr r8, [r12, #RESET_DATA(MASK_LP1)] + tst r8, r11 @ if in_lp1 + beq __is_not_lp1 + cmp r10, #0 + bne __die @ only CPU0 can be here + ldr lr, [r12, #RESET_DATA(STARTUP_LP1)] + cmp lr, #0 + bleq __die @ no LP1 startup handler + THUMB( add lr, lr, #1 ) @ switch to Thumb mode + bx lr +__is_not_lp1: + /* Waking up from LP2? */ ldr r9, [r12, #RESET_DATA(MASK_LP2)] tst r9, r11 @ if in_lp2 diff --git a/arch/arm/mach-tegra/reset.c b/arch/arm/mach-tegra/reset.c index 1ac434e..fd0bbf8 100644 --- a/arch/arm/mach-tegra/reset.c +++ b/arch/arm/mach-tegra/reset.c @@ -81,6 +81,8 @@ void __init tegra_cpu_reset_handler_init(void) #endif #ifdef CONFIG_PM_SLEEP + __tegra_cpu_reset_handler_data[TEGRA_RESET_STARTUP_LP1] = + TEGRA_IRAM_CODE_AREA; __tegra_cpu_reset_handler_data[TEGRA_RESET_STARTUP_LP2] = virt_to_phys((void *)tegra_resume); #endif -- 1.8.3.4 -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
