@@ -682,11 +682,19 @@ int get_msr(int cpu, int offset, unsigned long long *msr)
int retval;
char pathname[32];
int fd;
-
+#if defined(ANDROID)
+ sprintf(pathname, "/dev/msr%d", cpu);
+#else
sprintf(pathname, "/dev/cpu/%d/msr", cpu);
+#endif
fd = open(pathname, O_RDONLY);
if (fd < 0)
+#if defined(ANDROID)
+ err(-1, "%s open failed, try chown or chmod +r /dev/msr*, or run as root",
+ pathname);
+#else
err(-1, "%s open failed, try chown or chmod +r /dev/cpu/*/msr, or run as root", pathname);
+#endif
retval = pread(fd, msr, sizeof(*msr), offset);
if (retval != sizeof(*msr)) {
@@ -706,11 +714,19 @@ int put_msr(int cpu, int offset, unsigned long long new_msr)
char pathname[32];
int retval;
int fd;
-
+#if defined(ANDROID)
+ sprintf(pathname, "/dev/msr%d", cpu);
+#else
sprintf(pathname, "/dev/cpu/%d/msr", cpu);
+#endif
fd = open(pathname, O_RDWR);
if (fd < 0)
+#if defined(ANDROID)
+ err(-1, "%s open failed, try chown or chmod +r /dev//msr*, or run as root",
+ pathname);
+#else
err(-1, "%s open failed, try chown or chmod +r /dev/cpu/*/msr, or run as root", pathname);
+#endif
retval = pwrite(fd, &new_msr, sizeof(new_msr), offset);
if (retval != sizeof(new_msr))
@@ -1385,10 +1401,18 @@ void probe_dev_msr(void)
struct stat sb;
char pathname[32];
+#if defined(ANDROID)
+ sprintf(pathname, "/dev/msr%d", base_cpu);
+#else
sprintf(pathname, "/dev/cpu/%d/msr", base_cpu);
+#endif
if (stat(pathname, &sb))
if (system("/sbin/modprobe msr > /dev/null 2>&1"))
+#if defined(ANDROID)
+ err(-5, "no /dev/msr0, Try \"# modprobe msr\" ");
+#else
err(-5, "no /dev/cpu/0/msr, Try \"# modprobe msr\" ");
+#endif
}
static void get_cpuid_or_exit(unsigned int leaf,
This patch adds support for Android by updating the MSR device path handling in x86_energy_perf_policy. The code now uses /dev/msrN on Android systems instead of the default /dev/cpu/N/msr path. Error messages and modprobe instructions are also updated accordingly to improve clarity for Android users. Signed-off-by: Kaushlendra Kumar <kaushlendra.kumar@intel.com> --- .../x86_energy_perf_policy.c | 28 +++++++++++++++++-- 1 file changed, 26 insertions(+), 2 deletions(-)