[PATCH 5.19 056/192] drm/i915/slpc: Lets fix the PCODE min freq table setup for SLPC

Greg Kroah-Hartman
2022-09-13T14:14:31Z

From: Rodrigo Vivi <rodrigo.vivi@intel.com>

commit e1cab970574c001d83e59ca8388c474a57a1afb6 upstream.

We need to inform PCODE of a desired ring frequencies so PCODE update
the memory frequencies to us. rps->min_freq and rps->max_freq are the
frequencies used in that request. However they were unset when SLPC was
enabled and PCODE never updated the memory freq.

v2 (as Suggested by Ashutosh): if SLPC is in use, let's pick the right
frequencies from the get_ia_constants instead of the fake init of
rps' min and max.

v3: don't forget the max <= min return

v4: Move all the freq conversion to intel_rps.c. And the max <= min
check to where it belongs.

v5: (Ashutosh) Fix old comment s/50 HZ/50 MHz and add a doc explaining
the "raw format"

Fixes: 7ba79a671568 ("drm/i915/guc/slpc: Gate Host RPS when SLPC is enabled")
Cc: <stable@vger.kernel.org> # v5.15+
Cc: Ashutosh Dixit <ashutosh.dixit@intel.com>
Tested-by: Sushma Venkatesh Reddy <sushma.venkatesh.reddy@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220831214538.143950-1-rodrigo.vivi@intel.com
(cherry picked from commit 018a7bdbb090b9155a6509a0d1a684db4afaa5b1)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/gpu/drm/i915/gt/intel_llc.c | 19 ++++++-------
drivers/gpu/drm/i915/gt/intel_rps.c | 50 ++++++++++++++++++++++++++++++++++++
drivers/gpu/drm/i915/gt/intel_rps.h | 2 +
3 files changed, 61 insertions(+), 10 deletions(-)

--- a/drivers/gpu/drm/i915/gt/intel_llc.c
+++ b/drivers/gpu/drm/i915/gt/intel_llc.c
@@ -12,6 +12,7 @@
#include "intel_llc.h"
#include "intel_mchbar_regs.h"
#include "intel_pcode.h"
+#include "intel_rps.h"

struct ia_constants {
unsigned int min_gpu_freq;
@@ -55,9 +56,6 @@ static bool get_ia_constants(struct inte
if (!HAS_LLC(i915) || IS_DGFX(i915))
return false;

- if (rps->max_freq <= rps->min_freq)
- return false;
-
consts->max_ia_freq = cpu_max_MHz();

consts->min_ring_freq =
@@ -65,13 +63,8 @@ static bool get_ia_constants(struct inte
/* convert DDR frequency from units of 266.6MHz to bandwidth */
consts->min_ring_freq = mult_frac(consts->min_ring_freq, 8, 3);

- consts->min_gpu_freq = rps->min_freq;
- consts->max_gpu_freq = rps->max_freq;
- if (GRAPHICS_VER(i915) >= 9) {
- /* Convert GT frequency to 50 HZ units */
- consts->min_gpu_freq /= GEN9_FREQ_SCALER;
- consts->max_gpu_freq /= GEN9_FREQ_SCALER;
- }
+ consts->min_gpu_freq = intel_rps_get_min_raw_freq(rps);
+ consts->max_gpu_freq = intel_rps_get_max_raw_freq(rps);

return true;
}
@@ -132,6 +125,12 @@ static void gen6_update_ring_freq(struct
return;

/*
+ * Although this is unlikely on any platform during initialization,
+ * let's ensure we don't get accidentally into infinite loop
+ */
+ if (consts.max_gpu_freq <= consts.min_gpu_freq)
+ return;
+ /*
* For each potential GPU frequency, load a ring frequency we'd like
* to use for memory access. We do this by specifying the IA frequency
* the PCU should use as a reference to determine the ring frequency.
--- a/drivers/gpu/drm/i915/gt/intel_rps.c
+++ b/drivers/gpu/drm/i915/gt/intel_rps.c
@@ -2123,6 +2123,31 @@ u32 intel_rps_get_max_frequency(struct i
return intel_gpu_freq(rps, rps->max_freq_softlimit);
}

+/**
+ * intel_rps_get_max_raw_freq - returns the max frequency in some raw format.
+ * @rps: the intel_rps structure
+ *
+ * Returns the max frequency in a raw format. In newer platforms raw is in
+ * units of 50 MHz.
+ */
+u32 intel_rps_get_max_raw_freq(struct intel_rps *rps)
+{
+ struct intel_guc_slpc *slpc = rps_to_slpc(rps);
+ u32 freq;
+
+ if (rps_uses_slpc(rps)) {
+ return DIV_ROUND_CLOSEST(slpc->rp0_freq,
+ GT_FREQUENCY_MULTIPLIER);
+ } else {
+ freq = rps->max_freq;
+ if (GRAPHICS_VER(rps_to_i915(rps)) >= 9) {
+ /* Convert GT frequency to 50 MHz units */
+ freq /= GEN9_FREQ_SCALER;
+ }
+ return freq;
+ }
+}
+
u32 intel_rps_get_rp0_frequency(struct intel_rps *rps)
{
struct intel_guc_slpc *slpc = rps_to_slpc(rps);
@@ -2211,6 +2236,31 @@ u32 intel_rps_get_min_frequency(struct i
return intel_gpu_freq(rps, rps->min_freq_softlimit);
}

+/**
+ * intel_rps_get_min_raw_freq - returns the min frequency in some raw format.
+ * @rps: the intel_rps structure
+ *
+ * Returns the min frequency in a raw format. In newer platforms raw is in
+ * units of 50 MHz.
+ */
+u32 intel_rps_get_min_raw_freq(struct intel_rps *rps)
+{
+ struct intel_guc_slpc *slpc = rps_to_slpc(rps);
+ u32 freq;
+
+ if (rps_uses_slpc(rps)) {
+ return DIV_ROUND_CLOSEST(slpc->min_freq,
+ GT_FREQUENCY_MULTIPLIER);
+ } else {
+ freq = rps->min_freq;
+ if (GRAPHICS_VER(rps_to_i915(rps)) >= 9) {
+ /* Convert GT frequency to 50 MHz units */
+ freq /= GEN9_FREQ_SCALER;
+ }
+ return freq;
+ }
+}
+
static int set_min_freq(struct intel_rps *rps, u32 val)
{
int ret = 0;
--- a/drivers/gpu/drm/i915/gt/intel_rps.h
+++ b/drivers/gpu/drm/i915/gt/intel_rps.h
@@ -37,8 +37,10 @@ u32 intel_rps_get_cagf(struct intel_rps
u32 intel_rps_read_actual_frequency(struct intel_rps *rps);
u32 intel_rps_get_requested_frequency(struct intel_rps *rps);
u32 intel_rps_get_min_frequency(struct intel_rps *rps);
+u32 intel_rps_get_min_raw_freq(struct intel_rps *rps);
int intel_rps_set_min_frequency(struct intel_rps *rps, u32 val);
u32 intel_rps_get_max_frequency(struct intel_rps *rps);
+u32 intel_rps_get_max_raw_freq(struct intel_rps *rps);
int intel_rps_set_max_frequency(struct intel_rps *rps, u32 val);
u32 intel_rps_get_rp0_frequency(struct intel_rps *rps);
u32 intel_rps_get_rp1_frequency(struct intel_rps *rps);