diff options
| author | Venki Pallipadi <venkatesh.pallipadi@intel.com> | 2007-05-24 00:42:13 +0200 |
|---|---|---|
| committer | Dave Jones <davej@redhat.com> | 2007-05-29 22:56:40 +0200 |
| commit | 13424f6514f6444554a103362dd9d31eabbbdc54 (patch) | |
| tree | 158cc4af6254e7c707b508376f179ca971237597 /arch/i386/kernel/cpu | |
| parent | [CPUFREQ] check return value of sysfs_create_file (diff) | |
| download | linux-13424f6514f6444554a103362dd9d31eabbbdc54.tar.xz linux-13424f6514f6444554a103362dd9d31eabbbdc54.zip | |
[CPUFREQ] acpi-cpufreq: Proper ReadModifyWrite of PERF_CTL MSR
During recent acpi-cpufreq changes, writing to PERF_CTL msr
changed from RMW of entire 64 bit to RMW of low 32 bit and clearing of
upper 32 bit. Fix it back to do a proper RMW of the MSR.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Dave Jones <davej@redhat.com>
Diffstat (limited to 'arch/i386/kernel/cpu')
| -rw-r--r-- | arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.c | 13 |
1 files changed, 5 insertions, 8 deletions
diff --git a/arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.c b/arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.c index 10baa3501ed3..18c8b67ea3a7 100644 --- a/arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.c +++ b/arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.c @@ -167,11 +167,13 @@ static void do_drv_read(struct drv_cmd *cmd) static void do_drv_write(struct drv_cmd *cmd) { - u32 h = 0; + u32 lo, hi; switch (cmd->type) { case SYSTEM_INTEL_MSR_CAPABLE: - wrmsr(cmd->addr.msr.reg, cmd->val, h); + rdmsr(cmd->addr.msr.reg, lo, hi); + lo = (lo & ~INTEL_MSR_RANGE) | (cmd->val & INTEL_MSR_RANGE); + wrmsr(cmd->addr.msr.reg, lo, hi); break; case SYSTEM_IO_CAPABLE: acpi_os_write_port((acpi_io_address)cmd->addr.io.port, @@ -372,7 +374,6 @@ static int acpi_cpufreq_target(struct cpufreq_policy *policy, struct cpufreq_freqs freqs; cpumask_t online_policy_cpus; struct drv_cmd cmd; - unsigned int msr; unsigned int next_state = 0; /* Index into freq_table */ unsigned int next_perf_state = 0; /* Index into perf table */ unsigned int i; @@ -417,11 +418,7 @@ static int acpi_cpufreq_target(struct cpufreq_policy *policy, case SYSTEM_INTEL_MSR_CAPABLE: cmd.type = SYSTEM_INTEL_MSR_CAPABLE; cmd.addr.msr.reg = MSR_IA32_PERF_CTL; - msr = - (u32) perf->states[next_perf_state]. - control & INTEL_MSR_RANGE; - cmd.val = get_cur_val(online_policy_cpus); - cmd.val = (cmd.val & ~INTEL_MSR_RANGE) | msr; + cmd.val = (u32) perf->states[next_perf_state].control; break; case SYSTEM_IO_CAPABLE: cmd.type = SYSTEM_IO_CAPABLE; |