From 98e720f77dba6bb702a57f3d8479e6445e34f38c Mon Sep 17 00:00:00 2001 From: Jiaxun Yang Date: Sat, 25 Jan 2025 18:51:33 +0800 Subject: [PATCH] LoongArch: Derive timer max_delta from PRCFG1's timer_bits As per arch spec, maximum timer bits is configurable and should not be hardcoded in any way. Probe timer bits from PRCFG1 and use that to determine the clockevent's max_delta to be conformance. Signed-off-by: Jiaxun Yang Signed-off-by: Huacai Chen --- arch/loongarch/include/asm/cpu-info.h | 1 + arch/loongarch/include/asm/loongarch.h | 1 - arch/loongarch/kernel/cpu-probe.c | 1 + arch/loongarch/kernel/time.c | 2 +- 4 files changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/loongarch/include/asm/cpu-info.h b/arch/loongarch/include/asm/cpu-info.h index 900589cb159de..35e0a230a4849 100644 --- a/arch/loongarch/include/asm/cpu-info.h +++ b/arch/loongarch/include/asm/cpu-info.h @@ -57,6 +57,7 @@ struct cpuinfo_loongarch { int global_id; /* physical global thread number */ int vabits; /* Virtual Address size in bits */ int pabits; /* Physical Address size in bits */ + int timerbits; /* Width of arch timer in bits */ unsigned int ksave_mask; /* Usable KSave mask. */ unsigned int watch_dreg_count; /* Number data breakpoints */ unsigned int watch_ireg_count; /* Number instruction breakpoints */ diff --git a/arch/loongarch/include/asm/loongarch.h b/arch/loongarch/include/asm/loongarch.h index 64ad277e096ed..a3cc4f8d4c4a0 100644 --- a/arch/loongarch/include/asm/loongarch.h +++ b/arch/loongarch/include/asm/loongarch.h @@ -466,7 +466,6 @@ #define LOONGARCH_CSR_TCFG 0x41 /* Timer config */ #define CSR_TCFG_VAL_SHIFT 2 -#define CSR_TCFG_VAL_WIDTH 48 #define CSR_TCFG_VAL (_ULCAST_(0x3fffffffffff) << CSR_TCFG_VAL_SHIFT) #define CSR_TCFG_PERIOD_SHIFT 1 #define CSR_TCFG_PERIOD (_ULCAST_(0x1) << CSR_TCFG_PERIOD_SHIFT) diff --git a/arch/loongarch/kernel/cpu-probe.c b/arch/loongarch/kernel/cpu-probe.c index cbce099037b27..fedaa67cde410 100644 --- a/arch/loongarch/kernel/cpu-probe.c +++ b/arch/loongarch/kernel/cpu-probe.c @@ -190,6 +190,7 @@ static void cpu_probe_common(struct cpuinfo_loongarch *c) set_cpu_asid_mask(c, asid_mask); config = read_csr_prcfg1(); + c->timerbits = (config & CSR_CONF1_TMRBITS) >> CSR_CONF1_TMRBITS_SHIFT; c->ksave_mask = GENMASK((config & CSR_CONF1_KSNUM) - 1, 0); c->ksave_mask &= ~(EXC_KSAVE_MASK | PERCPU_KSAVE_MASK | KVM_KSAVE_MASK); diff --git a/arch/loongarch/kernel/time.c b/arch/loongarch/kernel/time.c index a07d7eff4dc5f..e2d3bfeb63664 100644 --- a/arch/loongarch/kernel/time.c +++ b/arch/loongarch/kernel/time.c @@ -132,7 +132,7 @@ int constant_clockevent_init(void) #else unsigned long min_delta = 1000; #endif - unsigned long max_delta = (1UL << 48) - 1; + unsigned long max_delta = GENMASK_ULL(boot_cpu_data.timerbits, 0); struct clock_event_device *cd; static int irq = 0, timer_irq_installed = 0; -- 2.39.5