From: Rick Wertenbroek rick.wertenbroek@gmail.com
commit 9dd3c7c4c8c3f7f010d9cdb7c3f42506d93c9527 upstream.
The RK3399 PCIe controller should wait until the PHY PLLs are locked. Add poll and timeout to wait for PHY PLLs to be locked. If they cannot be locked generate error message and jump to error handler. Accessing registers in the PHY clock domain when PLLs are not locked causes hang The PHY PLLs status is checked through a side channel register. This is documented in the TRM section 17.5.8.1 "PCIe Initialization Sequence".
Link: https://lore.kernel.org/r/20230418074700.1083505-5-rick.wertenbroek@gmail.co... Fixes: cf590b078391 ("PCI: rockchip: Add EP driver for Rockchip PCIe controller") Tested-by: Damien Le Moal dlemoal@kernel.org Signed-off-by: Rick Wertenbroek rick.wertenbroek@gmail.com Signed-off-by: Lorenzo Pieralisi lpieralisi@kernel.org Reviewed-by: Damien Le Moal dlemoal@kernel.org Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/pci/controller/pcie-rockchip.c | 17 +++++++++++++++++ drivers/pci/controller/pcie-rockchip.h | 2 ++ 2 files changed, 19 insertions(+)
--- a/drivers/pci/controller/pcie-rockchip.c +++ b/drivers/pci/controller/pcie-rockchip.c @@ -14,6 +14,7 @@ #include <linux/clk.h> #include <linux/delay.h> #include <linux/gpio/consumer.h> +#include <linux/iopoll.h> #include <linux/of_pci.h> #include <linux/phy/phy.h> #include <linux/platform_device.h> @@ -153,6 +154,12 @@ int rockchip_pcie_parse_dt(struct rockch } EXPORT_SYMBOL_GPL(rockchip_pcie_parse_dt);
+#define rockchip_pcie_read_addr(addr) rockchip_pcie_read(rockchip, addr) +/* 100 ms max wait time for PHY PLLs to lock */ +#define RK_PHY_PLL_LOCK_TIMEOUT_US 100000 +/* Sleep should be less than 20ms */ +#define RK_PHY_PLL_LOCK_SLEEP_US 1000 + int rockchip_pcie_init_port(struct rockchip_pcie *rockchip) { struct device *dev = rockchip->dev; @@ -254,6 +261,16 @@ int rockchip_pcie_init_port(struct rockc } }
+ err = readx_poll_timeout(rockchip_pcie_read_addr, + PCIE_CLIENT_SIDE_BAND_STATUS, + regs, !(regs & PCIE_CLIENT_PHY_ST), + RK_PHY_PLL_LOCK_SLEEP_US, + RK_PHY_PLL_LOCK_TIMEOUT_US); + if (err) { + dev_err(dev, "PHY PLLs could not lock, %d\n", err); + goto err_power_off_phy; + } + /* * Please don't reorder the deassert sequence of the following * four reset pins. --- a/drivers/pci/controller/pcie-rockchip.h +++ b/drivers/pci/controller/pcie-rockchip.h @@ -38,6 +38,8 @@ #define PCIE_CLIENT_MODE_EP HIWORD_UPDATE(0x0040, 0) #define PCIE_CLIENT_GEN_SEL_1 HIWORD_UPDATE(0x0080, 0) #define PCIE_CLIENT_GEN_SEL_2 HIWORD_UPDATE_BIT(0x0080) +#define PCIE_CLIENT_SIDE_BAND_STATUS (PCIE_CLIENT_BASE + 0x20) +#define PCIE_CLIENT_PHY_ST BIT(12) #define PCIE_CLIENT_DEBUG_OUT_0 (PCIE_CLIENT_BASE + 0x3c) #define PCIE_CLIENT_DEBUG_LTSSM_MASK GENMASK(5, 0) #define PCIE_CLIENT_DEBUG_LTSSM_L1 0x18