From ee490bcc4f2d456c40df93236cf6a1bce2d5ddd0 Mon Sep 17 00:00:00 2001 From: Magnus Damm Date: Sun, 15 Sep 2013 00:29:07 +0900 Subject: [PATCH] ARM: shmobile: Extend APMU code to allow single cluster only Extend the APMU code with a check to only allow boot of CPU cores that sit in the same cluster as CPU0. This makes it possible for people to use the r8a790 CA7 boot mode with CA7-cores only. The default CA15 boot mode will enable CA15 cores only. This is an intentional software limitation to cope with lacking scheduler support. By removing this patch it is possible to run all 8 cores in parallel, but this is not recommended without out of tree scheduler modfications or custom user space code to control the CPU affinitiy. Signed-off-by: Magnus Damm Signed-off-by: Simon Horman --- arch/arm/mach-shmobile/platsmp-apmu.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/arch/arm/mach-shmobile/platsmp-apmu.c b/arch/arm/mach-shmobile/platsmp-apmu.c index 34dc40dacb79..caaaa35b589f 100644 --- a/arch/arm/mach-shmobile/platsmp-apmu.c +++ b/arch/arm/mach-shmobile/platsmp-apmu.c @@ -94,8 +94,21 @@ static void apmu_parse_cfg(void (*fn)(struct resource *res, int cpu, int bit)) u32 id; int k; int bit, index; + bool is_allowed; for (k = 0; k < ARRAY_SIZE(apmu_config); k++) { + /* only enable the cluster that includes the boot CPU */ + is_allowed = false; + for (bit = 0; bit < ARRAY_SIZE(apmu_config[k].cpus); bit++) { + id = apmu_config[k].cpus[bit]; + if (id >= 0) { + if (id == cpu_logical_map(0)) + is_allowed = true; + } + } + if (!is_allowed) + continue; + for (bit = 0; bit < ARRAY_SIZE(apmu_config[k].cpus); bit++) { id = apmu_config[k].cpus[bit]; if (id >= 0) { -- GitLab