[PATCH v2 3/7] intel-speed-select: Add check for CascadeLake-N models

From: Prarit Bhargava
Date: Thu Oct 03 2019 - 08:11:27 EST


Three CascadeLake-N models (6252N, 6230N, and 5218N) have SST-PBF support.

Return an error if the CascadeLake processor is not one of these specific
models.

v2: Add is_clx_n_platform()

Signed-off-by: Prarit Bhargava <prarit@xxxxxxxxxx>
---
.../x86/intel-speed-select/isst-config.c | 44 ++++++++++++++++++-
1 file changed, 42 insertions(+), 2 deletions(-)

diff --git a/tools/power/x86/intel-speed-select/isst-config.c b/tools/power/x86/intel-speed-select/isst-config.c
index f4a23678416e..734a7960458c 100644
--- a/tools/power/x86/intel-speed-select/isst-config.c
+++ b/tools/power/x86/intel-speed-select/isst-config.c
@@ -23,6 +23,7 @@ static int debug_flag;
static FILE *outf;

static int cpu_model;
+static int cpu_stepping;

#define MAX_CPUS_IN_ONE_REQ 64
static short max_target_cpus;
@@ -72,7 +73,16 @@ void debug_printf(const char *format, ...)
va_end(args);
}

-static void update_cpu_model(void)
+
+int is_clx_n_platform(void)
+{
+ if (cpu_model == 0x55)
+ if (cpu_stepping == 0x6 || cpu_stepping == 0x7)
+ return 1;
+ return 0;
+}
+
+static int update_cpu_model(void)
{
unsigned int ebx, ecx, edx;
unsigned int fms, family;
@@ -82,6 +92,34 @@ static void update_cpu_model(void)
cpu_model = (fms >> 4) & 0xf;
if (family == 6 || family == 0xf)
cpu_model += ((fms >> 16) & 0xf) << 4;
+
+ cpu_stepping = fms & 0xf;
+
+ /* only three CascadeLake-N models are supported */
+ if (is_clx_n_platform()) {
+ FILE *fp;
+ size_t n;
+ char *line;
+ int ret = 1;
+
+ fp = fopen("/proc/cpuinfo", "r");
+ if (!fp)
+ err(-1, "cannot open /proc/cpuinfo\n");
+
+ while (getline(&line, &n, fp) > 0) {
+ if (strstr(line, "model name")) {
+ if (strstr(line, "6252N") ||
+ strstr(line, "6230N") ||
+ strstr(line, "5218N"))
+ ret = 0;
+ break;
+ }
+ }
+ free(line);
+ fclose(fp);
+ return ret;
+ }
+ return 0;
}

/* Open a file, and exit on failure */
@@ -1889,7 +1927,9 @@ static void cmdline(int argc, char **argv)
fprintf(stderr, "Feature name and|or command not specified\n");
exit(0);
}
- update_cpu_model();
+ ret = update_cpu_model();
+ if (ret)
+ err(-1, "Invalid CPU model (%d)\n", cpu_model);
printf("Intel(R) Speed Select Technology\n");
printf("Executing on CPU model:%d[0x%x]\n", cpu_model, cpu_model);
set_max_cpu_num();
--
2.18.1