On Mon, May 20, 2024 at 04:42:59PM +0900, Yoshihiro Shimoda wrote:
> Add support for r8a779g0 (R-Car V4H).
>
> This driver previously supported r8a779f0 (R-Car S4-8). PCIe features
> of both r8a779f0 and r8a779g0 are almost all the same. For example:
> - PCI Express Base Specification Revision 4.0
> - Root complex mode and endpoint mode are supported
> However, r8a779g0 requires specific firmware downloading, to
> initialize the PHY. Otherwise, the PCIe controller cannot work.
>
> The attached firmware file "104_PCIe_fw_addr_data_ver1.05.txt" in
> the manual is a text file. But, Renesas is not able to distribute
> the firmware freely. So, we require converting the text file
> to a binary before the driver runs by using the following script:
>
> $ awk '/^\s*0x[0-9A-Fa-f]{4}\s+0x[0-9A-Fa-f]{4}/ \
> { print substr($2,5,2) substr($2,3,2) }' \
> 104_PCIe_fw_addr_data_ver1.05.txt | xxd -p -r > \
> rcar_gen4_pcie.bin
> $ sha1sum rcar_gen4_pcie.bin
> 1d0bd4b189b4eb009f5d564b1f93a79112994945 rcar_gen4_pcie.bin
>
> Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
> ---
> drivers/pci/controller/dwc/pcie-rcar-gen4.c | 194 +++++++++++++++++++-
> 1 file changed, 193 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/pci/controller/dwc/pcie-rcar-gen4.c b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> index bcbf0a52890d..f766a9739e15 100644
> --- a/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> +++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c
> @@ -5,8 +5,10 @@
> */
>
> #include <linux/delay.h>
> +#include <linux/firmware.h>
> #include <linux/interrupt.h>
> #include <linux/io.h>
> +#include <linux/iopoll.h>
> #include <linux/module.h>
> #include <linux/of.h>
> #include <linux/pci.h>
> @@ -20,9 +22,10 @@
> /* Renesas-specific */
> /* PCIe Mode Setting Register 0 */
> #define PCIEMSR0 0x0000
> -#define BIFUR_MOD_SET_ON BIT(0)
> +#define APP_SRIS_MODE BIT(6)
> #define DEVICE_TYPE_EP 0
> #define DEVICE_TYPE_RC BIT(4)
> +#define BIFUR_MOD_SET_ON BIT(0)
>
> /* PCIe Interrupt Status 0 */
> #define PCIEINTSTS0 0x0084
> @@ -37,19 +40,36 @@
> #define PCIEDMAINTSTSEN 0x0314
> #define PCIEDMAINTSTSEN_INIT GENMASK(15, 0)
>
> +/* Port Logic Registers 89 */
> +#define PRTLGC89 0x0b70
> +
> +/* Port Logic Registers 90 */
> +#define PRTLGC90 0x0b74
> +
> /* PCIe Reset Control Register 1 */
> #define PCIERSTCTRL1 0x0014
> #define APP_HOLD_PHY_RST BIT(16)
> #define APP_LTSSM_ENABLE BIT(0)
>
> +/* PCIe Power Management Control */
> +#define PCIEPWRMNGCTRL 0x0070
> +#define APP_CLK_REQ_N BIT(11)
> +#define APP_CLK_PM_EN BIT(10)
> +
> #define RCAR_NUM_SPEED_CHANGE_RETRIES 10
> #define RCAR_MAX_LINK_SPEED 4
>
> #define RCAR_GEN4_PCIE_EP_FUNC_DBI_OFFSET 0x1000
> #define RCAR_GEN4_PCIE_EP_FUNC_DBI2_OFFSET 0x800
>
> +/* About the firmware, please refer to the commit log */
Which commit log? This is no useful info to the developers. Please add the
actual information about the firmware here (whatever you mentioned in the commit
message).
> +#define RCAR_GEN4_PCIE_FIRMWARE_NAME "rcar_gen4_pcie.bin"
> +#define RCAR_GEN4_PCIE_FIRMWARE_BASE_ADDR 0xc000
> +MODULE_FIRMWARE(RCAR_GEN4_PCIE_FIRMWARE_NAME);
> +
> struct rcar_gen4_pcie;
> struct rcar_gen4_pcie_drvdata {
> + void (*additional_common_init)(struct rcar_gen4_pcie *rcar);
> int (*ltssm_control)(struct rcar_gen4_pcie *rcar, bool enable);
> enum dw_pcie_device_mode mode;
> };
> @@ -57,6 +77,7 @@ struct rcar_gen4_pcie_drvdata {
> struct rcar_gen4_pcie {
> struct dw_pcie dw;
> void __iomem *base;
> + void __iomem *phy_base;
> struct platform_device *pdev;
> const struct rcar_gen4_pcie_drvdata *drvdata;
> };
> @@ -180,6 +201,9 @@ static int rcar_gen4_pcie_common_init(struct rcar_gen4_pcie *rcar)
> if (ret)
> goto err_unprepare;
>
> + if (rcar->drvdata->additional_common_init)
> + rcar->drvdata->additional_common_init(rcar);
> +
> return 0;
>
> err_unprepare:
> @@ -221,6 +245,10 @@ static void rcar_gen4_pcie_unprepare(struct rcar_gen4_pcie *rcar)
>
> static int rcar_gen4_pcie_get_resources(struct rcar_gen4_pcie *rcar)
> {
> + rcar->phy_base = devm_platform_ioremap_resource_byname(rcar->pdev, "phy");
> + if (IS_ERR(rcar->phy_base))
> + return PTR_ERR(rcar->phy_base);
> +
> /* Renesas-specific registers */
> rcar->base = devm_platform_ioremap_resource_byname(rcar->pdev, "app");
>
> @@ -514,6 +542,166 @@ static int r8a779f0_pcie_ltssm_control(struct rcar_gen4_pcie *rcar, bool enable)
> return 0;
> }
>
> +static void rcar_gen4_pcie_additional_common_init(struct rcar_gen4_pcie *rcar)
> +{
> + struct dw_pcie *dw = &rcar->dw;
> + u32 val;
> +
> + /*
> + * The SoC manual said the register setting is required. Otherwise,
> + * linkup failed.
This also can be dropped.
> + */
> + val = dw_pcie_readl_dbi(dw, PCIE_PORT_LANE_SKEW);
> + val &= ~PORT_LANE_SKEW_INSERT_MASK;
> + if (dw->num_lanes < 4)
> + val |= BIT(6);
> + dw_pcie_writel_dbi(dw, PCIE_PORT_LANE_SKEW, val);
> +
> + val = readl(rcar->base + PCIEPWRMNGCTRL);
> + val |= APP_CLK_REQ_N | APP_CLK_PM_EN;
> + writel(val, rcar->base + PCIEPWRMNGCTRL);
> +}
> +
> +static void rcar_gen4_pcie_phy_reg_update_bits(struct rcar_gen4_pcie *rcar,
> + u32 offset, u32 mask, u32 val)
> +{
> + u32 tmp;
> +
> + tmp = readl(rcar->phy_base + offset);
> + tmp &= ~mask;
> + tmp |= val;
Use FIELD_* macros to avoid using the shift value.
> + writel(tmp, rcar->phy_base + offset);
> +}
> +
> +static int rcar_gen4_pcie_reg_test_bit(struct rcar_gen4_pcie *rcar,
> + u32 offset, u32 mask)
> +{
> + struct dw_pcie *dw = &rcar->dw;
> +
> + if (dw_pcie_readl_dbi(dw, offset) & mask)
> + return -EAGAIN;
Here a comment like below could be added at the top of the function
definition.
/*
* SoC reference manual suggests checking port logic register bits
* during firmware write. If read returns non-zero value, then this
* function returns -EAGAIN indicating that the write needs to be done
* again. If read returns zero, then return 0 to indicate success.
*/
> +
> + return 0;
> +}
> +
> +static int rcar_gen4_pcie_download_phy_firmware(struct rcar_gen4_pcie *rcar)
> +{
> + /* The check_addr values are magical numbers in the datasheet */
> + const u32 check_addr[] = { 0x00101018, 0x00101118, 0x00101021, 0x00101121};
> + struct dw_pcie *dw = &rcar->dw;
> + const struct firmware *fw;
> + unsigned int i, timeout;
> + u32 data;
> + int ret;
> +
> + ret = request_firmware(&fw, RCAR_GEN4_PCIE_FIRMWARE_NAME, dw->dev);
> + if (ret) {
> + dev_err(dw->dev, "%s: Requesting firmware failed (%s)\n",
> + __func__, RCAR_GEN4_PCIE_FIRMWARE_NAME);
dev_err(dw->dev, "Failed to load firmware (%s): %d",
RCAR_GEN4_PCIE_FIRMWARE_NAME, ret);
> + return ret;
> + }
> +
> + for (i = 0; i < (fw->size / 2); i++) {
> + data = fw->data[(i * 2) + 1] << 8 | fw->data[i * 2];
> + timeout = 100;
> + do {
> + dw_pcie_writel_dbi(dw, PRTLGC89, RCAR_GEN4_PCIE_FIRMWARE_BASE_ADDR + i);
> + dw_pcie_writel_dbi(dw, PRTLGC90, data);
> + if (rcar_gen4_pcie_reg_test_bit(rcar, PRTLGC89, BIT(30)) >= 0)
Can the return value > 0?
> + break;
> + if (!(--timeout)) {
> + ret = -ETIMEDOUT;
> + goto exit;
> + }
> + usleep_range(100, 200);
> + } while (1);
> + }
> +
> + rcar_gen4_pcie_phy_reg_update_bits(rcar, 0x0f8, BIT(17), BIT(17));
> +
> + for (i = 0; i < ARRAY_SIZE(check_addr); i++) {
> + timeout = 100;
> + do {
> + dw_pcie_writel_dbi(dw, PRTLGC89, check_addr[i]);
> + ret = rcar_gen4_pcie_reg_test_bit(rcar, PRTLGC89, BIT(30));
> + ret |= rcar_gen4_pcie_reg_test_bit(rcar, PRTLGC90, BIT(0));
> + if (ret >= 0)
Same as above.
> + break;
> + if (!(--timeout)) {
> + ret = -ETIMEDOUT;
> + goto exit;
> + }
> + usleep_range(100, 200);
> + } while (1);
> + }
> +
> + ret = 0;
At this point, ret should be 0, right?
> +exit:
> + release_firmware(fw);
> +
> + return ret;
> +}
> +
> +static int rcar_gen4_pcie_ltssm_control(struct rcar_gen4_pcie *rcar, bool enable)
> +{
> + struct dw_pcie *dw = &rcar->dw;
> + u32 val;
> + int ret;
> +
> + if (!enable) {
> + val = readl(rcar->base + PCIERSTCTRL1);
There is no need to use 'readl/writel' here (which has the barrier), but since
this driver is already using them, I'm not asking to change it now. But please
consider switching to _relaxed variants in a separate series.
> + val &= ~APP_LTSSM_ENABLE;
> + writel(val, rcar->base + PCIERSTCTRL1);
> +
> + return 0;
> + }
> +
> + val = dw_pcie_readl_dbi(dw, PCIE_PORT_FORCE);
> + val |= PORT_FORCE_DO_DESKEW_FOR_SRIS;
> + dw_pcie_writel_dbi(dw, PCIE_PORT_FORCE, val);
> +
> + val = readl(rcar->base + PCIEMSR0);
> + val |= APP_SRIS_MODE;
> + writel(val, rcar->base + PCIEMSR0);
> +
> + /*
> + * The R-Car Gen4 documents don't describe the PHY registers' name.
Gen4 datasheet? or reference manual?
- Mani
--
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