Re: [PATCH v12 2/6] PCI: mediatek: Add new method to get shared pcie-cfg base address
From: Bjorn Helgaas <helgaas@kernel.org>
Date: 2021-08-27 16:46:38
Also in:
linux-arm-kernel, linux-devicetree, linux-mediatek, linux-pci
On Mon, Aug 23, 2021 at 11:27:56AM +0800, Chuanjia Liu wrote:
For the new dts format, add a new method to get shared pcie-cfg base address and use it to configure the PCIECFG controller
Rewrap this to fill 75 columns.
quoted hunk ↗ jump to hunk
Signed-off-by: Chuanjia Liu <redacted> Acked-by: Ryder Lee <ryder.lee@mediatek.com> --- drivers/pci/controller/pcie-mediatek.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+)diff --git a/drivers/pci/controller/pcie-mediatek.c b/drivers/pci/controller/pcie-mediatek.c index 25bee693834f..4296d9e04240 100644 --- a/drivers/pci/controller/pcie-mediatek.c +++ b/drivers/pci/controller/pcie-mediatek.c@@ -14,6 +14,7 @@ #include <linux/irqchip/chained_irq.h> #include <linux/irqdomain.h> #include <linux/kernel.h> +#include <linux/mfd/syscon.h> #include <linux/msi.h> #include <linux/module.h> #include <linux/of_address.h>@@ -23,6 +24,7 @@ #include <linux/phy/phy.h> #include <linux/platform_device.h> #include <linux/pm_runtime.h> +#include <linux/regmap.h> #include <linux/reset.h> #include "../pci.h"@@ -207,6 +209,7 @@ struct mtk_pcie_port { * struct mtk_pcie - PCIe host information * @dev: pointer to PCIe device * @base: IO mapped register base + * @cfg: IO mapped register map for PCIe config * @free_ck: free-run reference clock * @mem: non-prefetchable memory resource * @ports: pointer to PCIe port information@@ -215,6 +218,7 @@ struct mtk_pcie_port { struct mtk_pcie { struct device *dev; void __iomem *base; + struct regmap *cfg; struct clk *free_ck; struct list_head ports;@@ -682,6 +686,10 @@ static int mtk_pcie_startup_port_v2(struct mtk_pcie_port *port) val |= PCIE_CSR_LTSSM_EN(port->slot) | PCIE_CSR_ASPM_L1_EN(port->slot); writel(val, pcie->base + PCIE_SYS_CFG_V2); + } else if (pcie->cfg) { + val = PCIE_CSR_LTSSM_EN(port->slot) | + PCIE_CSR_ASPM_L1_EN(port->slot); + regmap_update_bits(pcie->cfg, PCIE_SYS_CFG_V2, val, val); } /* Assert all reset signals */@@ -985,6 +993,7 @@ static int mtk_pcie_subsys_powerup(struct mtk_pcie *pcie) struct device *dev = pcie->dev; struct platform_device *pdev = to_platform_device(dev); struct resource *regs; + struct device_node *cfg_node; int err; /* get shared registers, which are optional */@@ -995,6 +1004,14 @@ static int mtk_pcie_subsys_powerup(struct mtk_pcie *pcie) return PTR_ERR(pcie->base); } + cfg_node = of_find_compatible_node(NULL, NULL, + "mediatek,generic-pciecfg");
This looks wrong to me. IIUC, since we start at NULL, this searches the entire device tree for any node with compatible = "mediatek,generic-pciecfg" but we should only care about the specific device/node this driver claimed. Should this be part of the match data, i.e., struct mtk_pcie_soc?
+ if (cfg_node) {
+ pcie->cfg = syscon_node_to_regmap(cfg_node);
Other drivers in drivers/pci/controller/ use
syscon_regmap_lookup_by_phandle() (j721e, dra7xx, keystone,
layerscape, artpec6) or syscon_regmap_lookup_by_compatible() (imx6,
kirin, v3-semi).
You should do it the same way unless there's a need to be different.
It's also nice if you can use the same struct member name
("mtk_pcie.cfg") as other drivers. They're not all consistent, but I
don't see any other "cfg".
+ if (IS_ERR(pcie->cfg))
+ return PTR_ERR(pcie->cfg);
+ }
+
pcie->free_ck = devm_clk_get(dev, "free_ck");
if (IS_ERR(pcie->free_ck)) {
if (PTR_ERR(pcie->free_ck) == -EPROBE_DEFER)
--
2.18.0