6.12-stable review patch. If anyone has any objections, please let me know.
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From: Krzysztof Kozlowski krzysztof.kozlowski@linaro.org
[ Upstream commit 588257897058a0b1aa47912db4fe93c6ff5e3887 ]
PHY_CMN_CLK_CFG0 register is updated by the PHY driver and by two divider clocks from Common Clock Framework: devm_clk_hw_register_divider_parent_hw(). Concurrent access by the clocks side is protected with spinlock, however driver's side in restoring state is not. Restoring state is called from msm_dsi_phy_enable(), so there could be a path leading to concurrent and conflicting updates with clock framework.
Add missing lock usage on the PHY driver side, encapsulated in its own function so the code will be still readable.
While shuffling the code, define and use PHY_CMN_CLK_CFG0 bitfields to make the code more readable and obvious.
Fixes: 1ef7c99d145c ("drm/msm/dsi: add support for 7nm DSI PHY/PLL") Reviewed-by: Dmitry Baryshkov dmitry.baryshkov@linaro.org Reviewed-by: Abhinav Kumar quic_abhinavk@quicinc.com Signed-off-by: Krzysztof Kozlowski krzysztof.kozlowski@linaro.org Patchwork: https://patchwork.freedesktop.org/patch/637376/ Link: https://lore.kernel.org/r/20250214-drm-msm-phy-pll-cfg-reg-v3-1-0943b850722c... Signed-off-by: Abhinav Kumar quic_abhinavk@quicinc.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/msm/dsi/phy/dsi_phy_7nm.c | 14 ++++++++++++-- .../gpu/drm/msm/registers/display/dsi_phy_7nm.xml | 5 ++++- 2 files changed, 16 insertions(+), 3 deletions(-)
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 031446c87daec..25ca649de717e 100644 --- a/drivers/gpu/drm/msm/dsi/phy/dsi_phy_7nm.c +++ b/drivers/gpu/drm/msm/dsi/phy/dsi_phy_7nm.c @@ -372,6 +372,15 @@ static void dsi_pll_enable_pll_bias(struct dsi_pll_7nm *pll) ndelay(250); }
+static void dsi_pll_cmn_clk_cfg0_write(struct dsi_pll_7nm *pll, u32 val) +{ + unsigned long flags; + + spin_lock_irqsave(&pll->postdiv_lock, flags); + writel(val, pll->phy->base + REG_DSI_7nm_PHY_CMN_CLK_CFG0); + spin_unlock_irqrestore(&pll->postdiv_lock, flags); +} + static void dsi_pll_disable_global_clk(struct dsi_pll_7nm *pll) { u32 data; @@ -574,8 +583,9 @@ static int dsi_7nm_pll_restore_state(struct msm_dsi_phy *phy) val |= cached->pll_out_div; writel(val, pll_7nm->phy->pll_base + REG_DSI_7nm_PHY_PLL_PLL_OUTDIV_RATE);
- writel(cached->bit_clk_div | (cached->pix_clk_div << 4), - phy_base + REG_DSI_7nm_PHY_CMN_CLK_CFG0); + dsi_pll_cmn_clk_cfg0_write(pll_7nm, + DSI_7nm_PHY_CMN_CLK_CFG0_DIV_CTRL_3_0(cached->bit_clk_div) | + DSI_7nm_PHY_CMN_CLK_CFG0_DIV_CTRL_7_4(cached->pix_clk_div));
val = readl(phy_base + REG_DSI_7nm_PHY_CMN_CLK_CFG1); val &= ~0x3; diff --git a/drivers/gpu/drm/msm/registers/display/dsi_phy_7nm.xml b/drivers/gpu/drm/msm/registers/display/dsi_phy_7nm.xml index d54b72f924493..e0bf6e016b4ce 100644 --- a/drivers/gpu/drm/msm/registers/display/dsi_phy_7nm.xml +++ b/drivers/gpu/drm/msm/registers/display/dsi_phy_7nm.xml @@ -9,7 +9,10 @@ xsi:schemaLocation="https://gitlab.freedesktop.org/freedreno/ rules-fd.xsd"> <reg32 offset="0x00004" name="REVISION_ID1"/> <reg32 offset="0x00008" name="REVISION_ID2"/> <reg32 offset="0x0000c" name="REVISION_ID3"/> - <reg32 offset="0x00010" name="CLK_CFG0"/> + <reg32 offset="0x00010" name="CLK_CFG0"> + <bitfield name="DIV_CTRL_3_0" low="0" high="3" type="uint"/> + <bitfield name="DIV_CTRL_7_4" low="4" high="7" type="uint"/> + </reg32> <reg32 offset="0x00014" name="CLK_CFG1"/> <reg32 offset="0x00018" name="GLBL_CTRL"/> <reg32 offset="0x0001c" name="RBUF_CTRL"/>