From 064231e548d0ef90453081f424ced7b3ffffffe9 Mon Sep 17 00:00:00 2001 From: Paul Burton Date: Wed, 9 Jul 2014 12:48:18 +0100 Subject: [PATCH] MIPS: pm-cps: Prevent use of mips_cps_* without CPS SMP These symbols will not be defined when CONFIG_MIPS_CPS=n, but although the CPS_PM_POWER_GATED state will never be used in that case the compiler doesn't have enough information to figure that out. Add checks which evaluate to a constant false for CONFIG_MIPS_CPS=n cases in order to help the compiler out & eliminate the symbol references. Signed-off-by: Paul Burton Reviewed-by: Markos Chandras Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/7278/ Signed-off-by: Ralf Baechle --- arch/mips/include/asm/smp-cps.h | 12 ++++++++++-- arch/mips/kernel/pm-cps.c | 8 ++++++++ 2 files changed, 18 insertions(+), 2 deletions(-) diff --git a/arch/mips/include/asm/smp-cps.h b/arch/mips/include/asm/smp-cps.h index a06a08a9afc6..326c16ebd589 100644 --- a/arch/mips/include/asm/smp-cps.h +++ b/arch/mips/include/asm/smp-cps.h @@ -31,11 +31,19 @@ extern void mips_cps_core_init(void); extern struct vpe_boot_config *mips_cps_boot_vpes(void); -extern bool mips_cps_smp_in_use(void); - extern void mips_cps_pm_save(void); extern void mips_cps_pm_restore(void); +#ifdef CONFIG_MIPS_CPS + +extern bool mips_cps_smp_in_use(void); + +#else /* !CONFIG_MIPS_CPS */ + +static inline bool mips_cps_smp_in_use(void) { return false; } + +#endif /* !CONFIG_MIPS_CPS */ + #else /* __ASSEMBLY__ */ .extern mips_cps_bootcfg; diff --git a/arch/mips/kernel/pm-cps.c b/arch/mips/kernel/pm-cps.c index c4c2069d3a20..c409a5aef8ab 100644 --- a/arch/mips/kernel/pm-cps.c +++ b/arch/mips/kernel/pm-cps.c @@ -149,6 +149,10 @@ int cps_pm_enter_state(enum cps_pm_state state) /* Setup the VPE to run mips_cps_pm_restore when started again */ if (config_enabled(CONFIG_CPU_PM) && state == CPS_PM_POWER_GATED) { + /* Power gating relies upon CPS SMP */ + if (!mips_cps_smp_in_use()) + return -EINVAL; + core_cfg = &mips_cps_core_bootcfg[core]; vpe_cfg = &core_cfg->vpe_config[current_cpu_data.vpe_id]; vpe_cfg->pc = (unsigned long)mips_cps_pm_restore; @@ -376,6 +380,10 @@ static void * __init cps_gen_entry_code(unsigned cpu, enum cps_pm_state state) memset(relocs, 0, sizeof(relocs)); if (config_enabled(CONFIG_CPU_PM) && state == CPS_PM_POWER_GATED) { + /* Power gating relies upon CPS SMP */ + if (!mips_cps_smp_in_use()) + goto out_err; + /* * Save CPU state. Note the non-standard calling convention * with the return address placed in v0 to avoid clobbering -- GitLab