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ARM: exynos: MCPM: Restore big.LITTLE cpuidle support 

[ Upstream commit ea9dd8f61c ]

Call exynos_cpu_power_up(cpunr) unconditionally. This is needed by the
big.LITTLE cpuidle driver and has no side-effects on other code paths.

The additional soft-reset call during little core power up has been added
to properly boot all cores on the Exynos5422-based boards with secure
firmware (like Odroid XU3/XU4 family). This however broke big.LITTLE
CPUidle driver, which worked only on boards without secure firmware (like
Peach-Pit/Pi Chromebooks). Apply the workaround only when board is
running under secure firmware.

Fixes: 833b5794e3 ("ARM: EXYNOS: reset Little cores when cpu is up")
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
5.4-rM2-2.2.x-imx-squashed
Marek Szyprowski 2020-06-29 12:02:18 +02:00 committed by Greg Kroah-Hartman
parent 489ee1f219
commit 0155cd348b
1 changed files with 7 additions and 3 deletions
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10
arch/arm/mach-exynos/mcpm-exynos.c
View File

@ -26,6 +26,7 @@
#define EXYNOS5420_USE_L2_COMMON_UP_STATE BIT(30)
static void __iomem *ns_sram_base_addr __ro_after_init;
static bool secure_firmware __ro_after_init;
/*
* The common v7_exit_coherency_flush API could not be used because of the
@ -58,15 +59,16 @@ static void __iomem *ns_sram_base_addr __ro_after_init;
static int exynos_cpu_powerup(unsigned int cpu, unsigned int cluster)
{
unsigned int cpunr = cpu + (cluster * EXYNOS5420_CPUS_PER_CLUSTER);
bool state;
pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster);
if (cpu >= EXYNOS5420_CPUS_PER_CLUSTER ||
cluster >= EXYNOS5420_NR_CLUSTERS)
return -EINVAL;
if (!exynos_cpu_power_state(cpunr)) {
exynos_cpu_power_up(cpunr);
state = exynos_cpu_power_state(cpunr);
exynos_cpu_power_up(cpunr);
if (!state && secure_firmware) {
/*
* This assumes the cluster number of the big cores(Cortex A15)
* is 0 and the Little cores(Cortex A7) is 1.
@ -258,6 +260,8 @@ static int __init exynos_mcpm_init(void)
return -ENOMEM;
}
secure_firmware = exynos_secure_firmware_available();
/*
* To increase the stability of KFC reset we need to program
* the PMU SPARE3 register