From 4813dea9e272ba0a57c50b8d51d440dd8e3ccdd7 Mon Sep 17 00:00:00 2001 From: Manivannan Sadhasivam Date: Sat, 1 Nov 2025 09:59:40 +0530 Subject: [PATCH 1/2] dt-bindings: PCI: amlogic: Fix the register name of the DBI region Binding incorrectly specifies the 'DBI' region as 'ELBI'. DBI is a must have region for DWC controllers as it has the Root Port and controller specific registers, while ELBI has optional registers. Hence, fix the binding. Though this is an ABI break, this change is needed to accurately describe the PCI memory map. Fixes: 7cd210391101 ("dt-bindings: PCI: meson: add DT bindings for Amlogic Meson PCIe controller") Signed-off-by: Manivannan Sadhasivam Signed-off-by: Manivannan Sadhasivam Link: https://patch.msgid.link/20251101-pci-meson-fix-v1-1-c50dcc56ed6a@oss.qualcomm.com --- Documentation/devicetree/bindings/pci/amlogic,axg-pcie.yaml | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/Documentation/devicetree/bindings/pci/amlogic,axg-pcie.yaml b/Documentation/devicetree/bindings/pci/amlogic,axg-pcie.yaml index 79a21ba0f9fd..c8258ef40328 100644 --- a/Documentation/devicetree/bindings/pci/amlogic,axg-pcie.yaml +++ b/Documentation/devicetree/bindings/pci/amlogic,axg-pcie.yaml @@ -36,13 +36,13 @@ properties: reg: items: - - description: External local bus interface registers + - description: Data Bus Interface registers - description: Meson designed configuration registers - description: PCIe configuration space reg-names: items: - - const: elbi + - const: dbi - const: cfg - const: config @@ -113,7 +113,7 @@ examples: pcie: pcie@f9800000 { compatible = "amlogic,axg-pcie", "snps,dw-pcie"; reg = <0xf9800000 0x400000>, <0xff646000 0x2000>, <0xf9f00000 0x100000>; - reg-names = "elbi", "cfg", "config"; + reg-names = "dbi", "cfg", "config"; interrupts = ; clocks = <&pclk>, <&clk_port>, <&clk_phy>; clock-names = "pclk", "port", "general"; From eff0306b109f2d611e44f0155b0324f6cfec3ef4 Mon Sep 17 00:00:00 2001 From: Manivannan Sadhasivam Date: Sat, 1 Nov 2025 09:59:42 +0530 Subject: [PATCH 2/2] PCI: meson: Fix parsing the DBI register region First of all, the driver was parsing the 'dbi' register region as 'elbi'. This was due to DT mistakenly passing 'dbi' as 'elbi'. Since the DT is now fixed to supply 'dbi' region, this driver can rely on the DWC core driver to parse and map it. However, to support the old DTs, if the 'elbi' region is found in DT, parse and map the region as both 'dw_pcie::elbi_base' as 'dw_pcie::dbi_base'. This will allow the driver to work with both broken and fixed DTs. Also, skip parsing the 'elbi' region in DWC core if 'pci->elbi_base' was already populated. Fixes: 9c0ef6d34fdb ("PCI: amlogic: Add the Amlogic Meson PCIe controller driver") Fixes: c96992a24bec ("PCI: dwc: Add support for ELBI resource mapping") Reported-by: Linnaea Lavia Closes: https://lore.kernel.org/linux-pci/DM4PR05MB102707B8CDF84D776C39F22F2C7F0A@DM4PR05MB10270.namprd05.prod.outlook.com/ Signed-off-by: Manivannan Sadhasivam Signed-off-by: Manivannan Sadhasivam Tested-by: Neil Armstrong # on Bananapi-M2S Reviewed-by: Neil Armstrong Cc: stable@vger.kernel.org # 6.2 Link: https://patch.msgid.link/20251101-pci-meson-fix-v1-3-c50dcc56ed6a@oss.qualcomm.com --- drivers/pci/controller/dwc/pci-meson.c | 18 +++++++++++++++--- drivers/pci/controller/dwc/pcie-designware.c | 12 +++++++----- 2 files changed, 22 insertions(+), 8 deletions(-) diff --git a/drivers/pci/controller/dwc/pci-meson.c b/drivers/pci/controller/dwc/pci-meson.c index 787469d1b396..54b6a4196f17 100644 --- a/drivers/pci/controller/dwc/pci-meson.c +++ b/drivers/pci/controller/dwc/pci-meson.c @@ -108,10 +108,22 @@ static int meson_pcie_get_mems(struct platform_device *pdev, struct meson_pcie *mp) { struct dw_pcie *pci = &mp->pci; + struct resource *res; - pci->dbi_base = devm_platform_ioremap_resource_byname(pdev, "elbi"); - if (IS_ERR(pci->dbi_base)) - return PTR_ERR(pci->dbi_base); + /* + * For the broken DTs that supply 'dbi' as 'elbi', parse the 'elbi' + * region and assign it to both 'pci->elbi_base' and 'pci->dbi_space' so + * that the DWC core can skip parsing both regions. + */ + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "elbi"); + if (res) { + pci->elbi_base = devm_pci_remap_cfg_resource(pci->dev, res); + if (IS_ERR(pci->elbi_base)) + return PTR_ERR(pci->elbi_base); + + pci->dbi_base = pci->elbi_base; + pci->dbi_phys_addr = res->start; + } mp->cfg_base = devm_platform_ioremap_resource_byname(pdev, "cfg"); if (IS_ERR(mp->cfg_base)) diff --git a/drivers/pci/controller/dwc/pcie-designware.c b/drivers/pci/controller/dwc/pcie-designware.c index c644216995f6..06eca858eb1b 100644 --- a/drivers/pci/controller/dwc/pcie-designware.c +++ b/drivers/pci/controller/dwc/pcie-designware.c @@ -168,11 +168,13 @@ int dw_pcie_get_resources(struct dw_pcie *pci) } /* ELBI is an optional resource */ - res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "elbi"); - if (res) { - pci->elbi_base = devm_ioremap_resource(pci->dev, res); - if (IS_ERR(pci->elbi_base)) - return PTR_ERR(pci->elbi_base); + if (!pci->elbi_base) { + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "elbi"); + if (res) { + pci->elbi_base = devm_ioremap_resource(pci->dev, res); + if (IS_ERR(pci->elbi_base)) + return PTR_ERR(pci->elbi_base); + } } /* LLDD is supposed to manually switch the clocks and resets state */