Re: [PATCH v2 1/2] drm/msm/dsi: Use "ref" fw clock instead of global name for VCO parent

From: AngeloGioacchino Del Regno
Date: Thu Sep 02 2021 - 03:28:01 EST


Il 30/08/21 20:24, Marijn Suijten ha scritto:
All DSI PHY/PLL drivers were referencing their VCO parent clock by a
global name, most of which don't exist or have been renamed. These
clock drivers seem to function fine without that except the 14nm driver
for the sdm6xx [1].

At the same time all DTs provide a "ref" clock as per the requirements
of dsi-phy-common.yaml, but the clock is never used. This patchset puts
that clock to use without relying on a global clock name, so that all
dependencies are explicitly defined in DT (the firmware) in the end.

Note that msm8974 is the only board not providing this clock, and
apq8064 was providing the wrong clock (19.2MHz cxo instead of 27MHz
pxo). Both have been been addressed in separate patches that are
supposed to land well in advance of this patchset.

Furthermore not all board-DTs provided this clock initially but that
deficiency has been addressed in followup patches (see the Fixes:
below). Those commits seem to assume that the clock was used, while
nothing in history indicates that this "ref" clock was ever retrieved.

[1]: https://lore.kernel.org/linux-arm-msm/386db1a6-a1cd-3c7d-a88e-dc83f8a1be96@xxxxxxxxxxxxxx/

Fixes: 79e51645a1dd ("arm64: dts: qcom: msm8916: Set 'xo_board' as ref clock of the DSI PHY")
Fixes: 6969d1d9c615 ("ARM: dts: qcom-apq8064: Set 'cxo_board' as ref clock of the DSI PHY")
Fixes: 0c0e72705a33 ("arm64: dts: sdm845: Set 'bi_tcxo' as ref clock of the DSI PHYs")
Signed-off-by: Marijn Suijten <marijn.suijten@xxxxxxxxxxxxxx>

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxxx>

---
drivers/gpu/drm/msm/dsi/phy/dsi_phy_10nm.c | 4 +++-
drivers/gpu/drm/msm/dsi/phy/dsi_phy_14nm.c | 4 +++-
drivers/gpu/drm/msm/dsi/phy/dsi_phy_28nm.c | 4 +++-
drivers/gpu/drm/msm/dsi/phy/dsi_phy_28nm_8960.c | 4 +++-
drivers/gpu/drm/msm/dsi/phy/dsi_phy_7nm.c | 4 +++-
5 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/msm/dsi/phy/dsi_phy_10nm.c b/drivers/gpu/drm/msm/dsi/phy/dsi_phy_10nm.c
index e46b10fc793a..3cbb1f1475e8 100644
--- a/drivers/gpu/drm/msm/dsi/phy/dsi_phy_10nm.c
+++ b/drivers/gpu/drm/msm/dsi/phy/dsi_phy_10nm.c
@@ -562,7 +562,9 @@ static int pll_10nm_register(struct dsi_pll_10nm *pll_10nm, struct clk_hw **prov
char clk_name[32], parent[32], vco_name[32];
char parent2[32], parent3[32], parent4[32];
struct clk_init_data vco_init = {
- .parent_names = (const char *[]){ "xo" },
+ .parent_data = &(const struct clk_parent_data) {
+ .fw_name = "ref",
+ },
.num_parents = 1,
.name = vco_name,
.flags = CLK_IGNORE_UNUSED,
diff --git a/drivers/gpu/drm/msm/dsi/phy/dsi_phy_14nm.c b/drivers/gpu/drm/msm/dsi/phy/dsi_phy_14nm.c
index bb31230721bd..406470265408 100644
--- a/drivers/gpu/drm/msm/dsi/phy/dsi_phy_14nm.c
+++ b/drivers/gpu/drm/msm/dsi/phy/dsi_phy_14nm.c
@@ -804,7 +804,9 @@ static int pll_14nm_register(struct dsi_pll_14nm *pll_14nm, struct clk_hw **prov
{
char clk_name[32], parent[32], vco_name[32];
struct clk_init_data vco_init = {
- .parent_names = (const char *[]){ "xo" },
+ .parent_data = &(const struct clk_parent_data) {
+ .fw_name = "ref",
+ },
.num_parents = 1,
.name = vco_name,
.flags = CLK_IGNORE_UNUSED,
diff --git a/drivers/gpu/drm/msm/dsi/phy/dsi_phy_28nm.c b/drivers/gpu/drm/msm/dsi/phy/dsi_phy_28nm.c
index 2da673a2add6..8ee9c9c0548d 100644
--- a/drivers/gpu/drm/msm/dsi/phy/dsi_phy_28nm.c
+++ b/drivers/gpu/drm/msm/dsi/phy/dsi_phy_28nm.c
@@ -521,7 +521,9 @@ static int pll_28nm_register(struct dsi_pll_28nm *pll_28nm, struct clk_hw **prov
{
char clk_name[32], parent1[32], parent2[32], vco_name[32];
struct clk_init_data vco_init = {
- .parent_names = (const char *[]){ "xo" },
+ .parent_data = &(const struct clk_parent_data) {
+ .fw_name = "ref",
+ },
.num_parents = 1,
.name = vco_name,
.flags = CLK_IGNORE_UNUSED,
diff --git a/drivers/gpu/drm/msm/dsi/phy/dsi_phy_28nm_8960.c b/drivers/gpu/drm/msm/dsi/phy/dsi_phy_28nm_8960.c
index aaa37456f4ee..9662cb236468 100644
--- a/drivers/gpu/drm/msm/dsi/phy/dsi_phy_28nm_8960.c
+++ b/drivers/gpu/drm/msm/dsi/phy/dsi_phy_28nm_8960.c
@@ -385,7 +385,9 @@ static int pll_28nm_register(struct dsi_pll_28nm *pll_28nm, struct clk_hw **prov
{
char *clk_name, *parent_name, *vco_name;
struct clk_init_data vco_init = {
- .parent_names = (const char *[]){ "pxo" },
+ .parent_data = &(const struct clk_parent_data) {
+ .fw_name = "ref",
+ },
.num_parents = 1,
.flags = CLK_IGNORE_UNUSED,
.ops = &clk_ops_dsi_pll_28nm_vco,
diff --git a/drivers/gpu/drm/msm/dsi/phy/dsi_phy_7nm.c b/drivers/gpu/drm/msm/dsi/phy/dsi_phy_7nm.c
index 7c23d4c47338..c77c30628cca 100644
--- a/drivers/gpu/drm/msm/dsi/phy/dsi_phy_7nm.c
+++ b/drivers/gpu/drm/msm/dsi/phy/dsi_phy_7nm.c
@@ -590,7 +590,9 @@ static int pll_7nm_register(struct dsi_pll_7nm *pll_7nm, struct clk_hw **provide
char clk_name[32], parent[32], vco_name[32];
char parent2[32], parent3[32], parent4[32];
struct clk_init_data vco_init = {
- .parent_names = (const char *[]){ "bi_tcxo" },
+ .parent_data = &(const struct clk_parent_data) {
+ .fw_name = "ref",
+ },
.num_parents = 1,
.name = vco_name,
.flags = CLK_IGNORE_UNUSED,