From: Stephen Warren <swarren@xxxxxxxxxx> Configure the clock controller to set an alternate clock for the CPU when it receives an IRQ during LP1 (system suspend). Specifically, use clk_m (the crystal) rather than clk_s (a 32KHz clock). Such an IRQ will be the LP1 wake event. This reduces the amount of time taken to resume from LP1. NVIDIA's downstream kernel executes this code on both Tegra30 and Tegra124, so it appears OK to make this change unconditionally. Signed-off-by: Stephen Warren <swarren@xxxxxxxxxx> --- arch/arm/mach-tegra/sleep-tegra30.S | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/arch/arm/mach-tegra/sleep-tegra30.S b/arch/arm/mach-tegra/sleep-tegra30.S index 6191f9456288..ba5e9c07d1b6 100644 --- a/arch/arm/mach-tegra/sleep-tegra30.S +++ b/arch/arm/mach-tegra/sleep-tegra30.S @@ -670,8 +670,12 @@ tegra30_switch_cpu_to_clk32k: pll_iddq_entry r1, r5, CLK_RESET_PLLX_MISC3, CLK_RESET_PLLX_MISC3_IDDQ _no_pll_in_iddq: - /* switch to CLKS */ - mov r0, #0 /* brust policy = 32KHz */ + /* + * Switch to clk_s (32KHz); bits 28:31=0 + * Enable burst on CPU IRQ; bit 24=1 + * Set IRQ burst clock source to clk_m; bits 10:8=0 + */ + mov r0, #(1 << 24) str r0, [r5, #CLK_RESET_SCLK_BURST] ret lr -- 2.23.0
