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".
Fixes: cf590b078391 ("PCI: rockchip: Add EP driver for Rockchip PCIe controller")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Rick Wertenbroek <rick.wertenbroek@xxxxxxxxx>
---
drivers/pci/controller/pcie-rockchip.c | 16 ++++++++++++++++
drivers/pci/controller/pcie-rockchip.h | 2 ++
2 files changed, 18 insertions(+)
diff --git a/drivers/pci/controller/pcie-rockchip.c b/drivers/pci/controller/pcie-rockchip.c
index 990a00e08..5f2e2dd5d 100644
--- 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 rockchip_pcie *rockchip)
}
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 +261,15 @@ int rockchip_pcie_init_port(struct rockchip_pcie *rockchip)
}
}
+ 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.
diff --git a/drivers/pci/controller/pcie-rockchip.h b/drivers/pci/controller/pcie-rockchip.h
index 51a123e5c..f3a5ff1cf 100644
--- 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
--
2.25.1
