This is a note to let you know that I've just added the patch titled
PCI: rockchip: Add poll and timeout to wait for PHY PLLs to be locked
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
pci-rockchip-add-poll-and-timeout-to-wait-for-phy-plls-to-be-locked.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 9dd3c7c4c8c3f7f010d9cdb7c3f42506d93c9527 Mon Sep 17 00:00:00 2001
From: Rick Wertenbroek <rick.wertenbroek@xxxxxxxxx>
Date: Tue, 18 Apr 2023 09:46:51 +0200
Subject: PCI: rockchip: Add poll and timeout to wait for PHY PLLs to be locked
From: Rick Wertenbroek <rick.wertenbroek@xxxxxxxxx>
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@xxxxxxxxx
Fixes: cf590b078391 ("PCI: rockchip: Add EP driver for Rockchip PCIe controller")
Tested-by: Damien Le Moal <dlemoal@xxxxxxxxxx>
Signed-off-by: Rick Wertenbroek <rick.wertenbroek@xxxxxxxxx>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@xxxxxxxxxx>
Reviewed-by: Damien Le Moal <dlemoal@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
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>
@@ -154,6 +155,12 @@ 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;
@@ -255,6 +262,16 @@ 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
@@ -37,6 +37,8 @@
#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
Patches currently in stable-queue which might be from rick.wertenbroek@xxxxxxxxx are
queue-5.4/pci-rockchip-use-u32-variable-to-access-32-bit-registers.patch
queue-5.4/pci-rockchip-assert-pci-configuration-enable-bit-after-probe.patch
queue-5.4/pci-rockchip-fix-legacy-irq-generation-for-rk3399-pcie-endpoint-core.patch
queue-5.4/pci-rockchip-add-poll-and-timeout-to-wait-for-phy-plls-to-be-locked.patch
queue-5.4/pci-rockchip-write-pci-device-id-to-correct-register.patch
queue-5.4/pci-rockchip-set-address-alignment-for-endpoint-mode.patch
