[igt-dev] [PATCH i-g-t v13 6/6] tests/i915/i915_pm_dc:Skip the DC6 test if BIOS has disabled PC8+

[Anshuman Gupta]

On 2019-09-03 at 17:38:02 +0300, Imre Deak wrote:
> On Sun, Sep 01, 2019 at 07:50:01PM +0530, Anshuman Gupta wrote:
> > As DC6 requires platform to enter PC8 package C state.
> > It make sense to skip the DC6 igt-test, if BIOS configuration
> > has disabled PC8+ package C states.
> > 
> > Signed-off-by: Anshuman Gupta <anshuman.gupta at intel.com>
> > ---
> >  tests/i915/i915_pm_dc.c | 55 +++++++++++++++++++++++++++++++++++++++++
> >  1 file changed, 55 insertions(+)
> > 
> > diff --git a/tests/i915/i915_pm_dc.c b/tests/i915/i915_pm_dc.c
> > index 4c7e152a..0b29599b 100644
> > --- a/tests/i915/i915_pm_dc.c
> > +++ b/tests/i915/i915_pm_dc.c
> > @@ -26,19 +26,35 @@
> >  #include "igt_sysfs.h"
> >  #include "igt_psr.h"
> >  #include <errno.h>
> > +#include <fcntl.h>
> >  #include <stdbool.h>
> >  #include <stdio.h>
> >  #include <string.h>
> >  #include "intel_bufmgr.h"
> >  #include "intel_io.h"
> >  #include "limits.h"
> > +#include "igt_kmod.h"
> >  
> >  /* DC State Flags */
> >  #define CHECK_DC5	1
> >  #define CHECK_DC6	2
> >  
> > +#define MSR_PKG_CST_CONFIG_CONTROL	0xE2
> > +/*
> > + * Below PKG CST limit mask and PC8 bits are meant for
> > + * HSW,BDW SKL,ICL and Goldmont Microarch and future platforms.
> > + * Refer IA S/W developers manual vol3c part3 chapter:35
> > + */
> > +#define  PKG_CST_LIMIT_MASK		0xF
> > +#define  PKG_CST_LIMIT_C8		0x6
> > +
> > +#define MSR_PC8_RES	0x630
> > +#define MSR_PC9_RES	0x631
> > +#define MSR_PC10_RES	0x632
> > +
> >  typedef struct {
> >  	int drm_fd;
> > +	int msr_fd;
> >  	int debugfs_fd;
> >  	uint32_t devid;
> >  	igt_display_t display;
> > @@ -52,6 +68,34 @@ typedef struct {
> >  static bool dc_state_wait_entry(int drm_fd, int dc_flag, int prev_dc_count);
> >  static void check_dc_counter(int drm_fd, int dc_flag, uint32_t prev_dc_count);
> >  
> > +/* If the read fails, then the machine doesn't support PC8+ residencies. */
> > +static bool supports_pc8_plus_residencies(data_t *data)
> > +{
> > +	int rc;
> > +	uint64_t val;
> > +	int msr_fd = data->msr_fd;
> > +
> > +	rc = pread(msr_fd, &val, sizeof(uint64_t), MSR_PC8_RES);
> > +	if (rc != sizeof(val))
> > +		return false;
> > +	rc = pread(msr_fd, &val, sizeof(uint64_t), MSR_PC9_RES);
> > +	if (rc != sizeof(val))
> > +		return false;
> > +	rc = pread(msr_fd, &val, sizeof(uint64_t), MSR_PC10_RES);
> > +	if (rc != sizeof(val))
> > +		return false;
> > +
> > +	rc = pread(msr_fd, &val, sizeof(uint64_t), MSR_PKG_CST_CONFIG_CONTROL);
> > +	if (rc != sizeof(val))
> > +		return false;
> > +	if ((val & PKG_CST_LIMIT_MASK) < PKG_CST_LIMIT_C8) {
> > +		igt_info("PKG C-states limited below PC8 by the BIOS\n");
> > +		return false;
> > +	}
> > +
> > +	return true;
> > +}
> 
> I missed it last time, but this is a copy/paste from i915_pm_rpm, so
> please factor it out instead into a lib function.
msr_fd is spread pretty sparse in i915_pm_rpm, passing it to a lib function 
doesn't sounds good, can we take it in a seperate patch, rather then this series?
> 
> > +
> >  static void setup_output(data_t *data)
> >  {
> >  	igt_display_t *display = &data->display;
> > @@ -255,6 +299,12 @@ int main(int argc, char *argv[])
> >  		igt_require(has_runtime_pm);
> >  		igt_require(igt_pm_dmc_loaded(data.debugfs_fd));
> >  		igt_display_require(&data.display, data.drm_fd);
> > +		/* Make sure our Kernel supports MSR and the module is loaded */
> > +		igt_require(igt_kmod_load("msr", NULL) == 0);
> > +
> > +		data.msr_fd = open("/dev/cpu/0/msr", O_RDONLY);
> > +		igt_assert_f(data.msr_fd >= 0,
> > +			     "Can't open /dev/cpu/0/msr.\n");
> >  	}
> >  
> >  	igt_subtest("dc5-psr") {
> > @@ -270,6 +320,8 @@ int main(int argc, char *argv[])
> >  		psr_enable(data.debugfs_fd, data.op_psr_mode);
> >  		igt_require_f(edp_psr_sink_support(&data),
> >  			      "Sink does not support PSR\n");
> > +		igt_require_f(supports_pc8_plus_residencies(&data),
> > +			      "PC8+ residencies not supported\n");
> >  		test_dc_state_psr(&data, CHECK_DC6);
> >  	}
> >  
> > @@ -278,11 +330,14 @@ int main(int argc, char *argv[])
> >  	}
> >  
> >  	igt_subtest("dc6-dpms") {
> > +		igt_require_f(supports_pc8_plus_residencies(&data),
> > +			      "PC8+ residencies not supported\n");
> >  		test_dc_state_dpms(&data, CHECK_DC6);
> >  	}
> >  
> >  	igt_fixture {
> >  		close(data.debugfs_fd);
> > +		close(data.msr_fd);
> >  		display_fini(&data);
> >  	}
> >  
> > -- 
> > 2.21.0
> >