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.
> Signed-off-by: Chuanjia Liu <chuanjia.liu@xxxxxxxxxxxx>
> Acked-by: Ryder Lee <ryder.lee@xxxxxxxxxxxx>
> ---
> 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
>
