From a895dc47ceba63feb711905440585cf2b16e9ce2 Mon Sep 17 00:00:00 2001 From: AngeloGioacchino Del Regno Date: Thu, 3 Jul 2025 14:08:45 +0200 Subject: [PATCH 1/3] PCI: mediatek-gen3: Implement sys clock ready time setting In preparation to add support for the PCI-Express Gen3 controller found in newer MediaTek SoCs, such as the Dimensity 9400 MT6991 and the MT8196 Chromebook SoC, add the definition for the PCIE Resource Control register and a new sys_clk_rdy_time_us variable in platform data. If sys_clk_rdy_time_us is found (> 0), set the new value in the aforementioned register only after configuring the controller to RC mode, as this may otherwise be reset. Overriding the register defaults for SYS_CLK_RDY_TIME allows to work around sys_clk_rdy signal glitching in MT6991 and MT8196. Signed-off-by: AngeloGioacchino Del Regno [mani: used FIELD_MODIFY() to simplify mask and update] Signed-off-by: Manivannan Sadhasivam Link: https://patch.msgid.link/20250703120847.121826-2-angelogioacchino.delregno@collabora.com --- drivers/pci/controller/pcie-mediatek-gen3.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/drivers/pci/controller/pcie-mediatek-gen3.c b/drivers/pci/controller/pcie-mediatek-gen3.c index 97147f43e41c..aa7bd22b144c 100644 --- a/drivers/pci/controller/pcie-mediatek-gen3.c +++ b/drivers/pci/controller/pcie-mediatek-gen3.c @@ -102,6 +102,9 @@ #define PCIE_MSI_SET_ADDR_HI_BASE 0xc80 #define PCIE_MSI_SET_ADDR_HI_OFFSET 0x04 +#define PCIE_RESOURCE_CTRL_REG 0xd2c +#define PCIE_RSRC_SYS_CLK_RDY_TIME_MASK GENMASK(7, 0) + #define PCIE_ICMD_PM_REG 0x198 #define PCIE_TURN_OFF_LINK BIT(4) @@ -149,6 +152,7 @@ enum mtk_gen3_pcie_flags { * struct mtk_gen3_pcie_pdata - differentiate between host generations * @power_up: pcie power_up callback * @phy_resets: phy reset lines SoC data. + * @sys_clk_rdy_time_us: System clock ready time override (microseconds) * @flags: pcie device flags. */ struct mtk_gen3_pcie_pdata { @@ -157,6 +161,7 @@ struct mtk_gen3_pcie_pdata { const char *id[MAX_NUM_PHY_RESETS]; int num_resets; } phy_resets; + u8 sys_clk_rdy_time_us; u32 flags; }; @@ -435,6 +440,14 @@ static int mtk_pcie_startup_port(struct mtk_gen3_pcie *pcie) writel_relaxed(val, pcie->base + PCIE_CONF_LINK2_CTL_STS); } + /* If parameter is present, adjust SYS_CLK_RDY_TIME to avoid glitching */ + if (pcie->soc->sys_clk_rdy_time_us) { + val = readl_relaxed(pcie->base + PCIE_RESOURCE_CTRL_REG); + FIELD_MODIFY(PCIE_RSRC_SYS_CLK_RDY_TIME_MASK, &val, + pcie->soc->sys_clk_rdy_time_us); + writel_relaxed(val, pcie->base + PCIE_RESOURCE_CTRL_REG); + } + /* Set class code */ val = readl_relaxed(pcie->base + PCIE_PCI_IDS_1); val &= ~GENMASK(31, 8); From 0106b6c114cf8b77d801d9e280b221f8b4d5595b Mon Sep 17 00:00:00 2001 From: AngeloGioacchino Del Regno Date: Thu, 3 Jul 2025 14:08:46 +0200 Subject: [PATCH 2/3] dt-bindings: PCI: mediatek-gen3: Add support for MT6991/MT8196 Add compatible strings for MT8196 and MT6991 (which are fully compatible between each other) and clock definitions. These new SoCs don't have tl_96m and tl_32k clocks, but need an AHB to APB bus clock and a low power clock. Signed-off-by: AngeloGioacchino Del Regno [mani: changed 'maxItems' to 'minItems' for reset] Signed-off-by: Manivannan Sadhasivam Reviewed-by: Krzysztof Kozlowski Link: https://patch.msgid.link/20250703120847.121826-3-angelogioacchino.delregno@collabora.com --- .../bindings/pci/mediatek-pcie-gen3.yaml | 35 +++++++++++++++++++ 1 file changed, 35 insertions(+) diff --git a/Documentation/devicetree/bindings/pci/mediatek-pcie-gen3.yaml b/Documentation/devicetree/bindings/pci/mediatek-pcie-gen3.yaml index 162406e0691a..0278845701ce 100644 --- a/Documentation/devicetree/bindings/pci/mediatek-pcie-gen3.yaml +++ b/Documentation/devicetree/bindings/pci/mediatek-pcie-gen3.yaml @@ -52,7 +52,12 @@ properties: - mediatek,mt8188-pcie - mediatek,mt8195-pcie - const: mediatek,mt8192-pcie + - items: + - enum: + - mediatek,mt6991-pcie + - const: mediatek,mt8196-pcie - const: mediatek,mt8192-pcie + - const: mediatek,mt8196-pcie - const: airoha,en7581-pcie reg: @@ -212,6 +217,36 @@ allOf: mediatek,pbus-csr: false + - if: + properties: + compatible: + contains: + enum: + - mediatek,mt8196-pcie + then: + properties: + clocks: + minItems: 6 + + clock-names: + items: + - const: pl_250m + - const: tl_26m + - const: bus + - const: low_power + - const: peri_26m + - const: peri_mem + + resets: + minItems: 2 + + reset-names: + items: + - const: phy + - const: mac + + mediatek,pbus-csr: false + - if: properties: compatible: From 81fedb39a9f0da301a11c7a3b81d91c3b9024462 Mon Sep 17 00:00:00 2001 From: AngeloGioacchino Del Regno Date: Thu, 3 Jul 2025 14:08:47 +0200 Subject: [PATCH 3/3] PCI: mediatek-gen3: Add support for MediaTek MT8196 SoC Introduce support for the PCI-Express Gen3 controller found in the MT8196 (and MT6991) SoC by adding a compatible string and platform specific data. Signed-off-by: AngeloGioacchino Del Regno Signed-off-by: Manivannan Sadhasivam Link: https://patch.msgid.link/20250703120847.121826-4-angelogioacchino.delregno@collabora.com --- drivers/pci/controller/pcie-mediatek-gen3.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/pci/controller/pcie-mediatek-gen3.c b/drivers/pci/controller/pcie-mediatek-gen3.c index aa7bd22b144c..75ddb8bee168 100644 --- a/drivers/pci/controller/pcie-mediatek-gen3.c +++ b/drivers/pci/controller/pcie-mediatek-gen3.c @@ -1340,6 +1340,15 @@ static const struct mtk_gen3_pcie_pdata mtk_pcie_soc_mt8192 = { }, }; +static const struct mtk_gen3_pcie_pdata mtk_pcie_soc_mt8196 = { + .power_up = mtk_pcie_power_up, + .phy_resets = { + .id[0] = "phy", + .num_resets = 1, + }, + .sys_clk_rdy_time_us = 10, +}; + static const struct mtk_gen3_pcie_pdata mtk_pcie_soc_en7581 = { .power_up = mtk_pcie_en7581_power_up, .phy_resets = { @@ -1354,6 +1363,7 @@ static const struct mtk_gen3_pcie_pdata mtk_pcie_soc_en7581 = { static const struct of_device_id mtk_pcie_of_match[] = { { .compatible = "airoha,en7581-pcie", .data = &mtk_pcie_soc_en7581 }, { .compatible = "mediatek,mt8192-pcie", .data = &mtk_pcie_soc_mt8192 }, + { .compatible = "mediatek,mt8196-pcie", .data = &mtk_pcie_soc_mt8196 }, {}, }; MODULE_DEVICE_TABLE(of, mtk_pcie_of_match);