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[CPUFREQ] acpi-cpufreq: Proper ReadModifyWrite of PERF_CTL MSR

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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>
This commit is contained in:
Venki Pallipadi 2007-05-23 15:42:13 -07:00 committed by Dave Jones
parent 0a4b2ccc55
commit 13424f6514
1 changed files with 5 additions and 8 deletions
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13
arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.c
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@ -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;