Print current LTSSM state when PCIe link down instead of the register
value, make it easier to get the link status.
Signed-off-by: Jianjun Wang <jianjun.wang@xxxxxxxxxxxx>
---
drivers/pci/controller/pcie-mediatek-gen3.c | 40 ++++++++++++++++++++-
1 file changed, 39 insertions(+), 1 deletion(-)
diff --git a/drivers/pci/controller/pcie-mediatek-gen3.c b/drivers/pci/controller/pcie-mediatek-gen3.c
index 7705d61fba4c..54663f025e27 100644
--- a/drivers/pci/controller/pcie-mediatek-gen3.c
+++ b/drivers/pci/controller/pcie-mediatek-gen3.c
@@ -153,6 +153,37 @@ struct mtk_gen3_pcie {
DECLARE_BITMAP(msi_irq_in_use, PCIE_MSI_IRQS_NUM);
};
+/* LTSSM state in PCIE_LTSSM_STATUS_REG bit[28:24] */
+static const char *const ltssm_str[] = {
+ "detect.quiet", /* 0x00 */
+ "detect.active", /* 0x01 */
+ "polling.active", /* 0x02 */
+ "polling.compliance", /* 0x03 */
+ "polling.configuration", /* 0x04 */
+ "config.linkwidthstart", /* 0x05 */
+ "config.linkwidthaccept", /* 0x06 */
+ "config.lanenumwait", /* 0x07 */
+ "config.lanenumaccept", /* 0x08 */
+ "config.complete", /* 0x09 */
+ "config.idle", /* 0x0A */
+ "recovery.receiverlock", /* 0x0B */
+ "recovery.equalization", /* 0x0C */
+ "recovery.speed", /* 0x0D */
+ "recovery.receiverconfig", /* 0x0E */
+ "recovery.idle", /* 0x0F */
+ "L0", /* 0x10 */
+ "L0s", /* 0x11 */
+ "L1.entry", /* 0x12 */
+ "L1.idle", /* 0x13 */
+ "L2.idle", /* 0x14 */
+ "L2.transmitwake", /* 0x15 */
+ "disable", /* 0x16 */
+ "loopback.entry", /* 0x17 */
+ "loopback.active", /* 0x18 */
+ "loopback.exit", /* 0x19 */
+ "hotreset", /* 0x1A */
+};
+
/**
* mtk_pcie_config_tlp_header() - Configure a configuration TLP header
* @bus: PCI bus to query
@@ -327,8 +358,15 @@ static int mtk_pcie_startup_port(struct mtk_gen3_pcie *pcie)
!!(val & PCIE_PORT_LINKUP), 20,
PCI_PM_D3COLD_WAIT * USEC_PER_MSEC);
if (err) {
+ const char *ltssm_state;
+ int ltssm_index;
+
val = readl_relaxed(pcie->base + PCIE_LTSSM_STATUS_REG);
- dev_err(pcie->dev, "PCIe link down, ltssm reg val: %#x\n", val);
+ ltssm_index = PCIE_LTSSM_STATE(val);
+ ltssm_state = ltssm_index >= ARRAY_SIZE(ltssm_str) ?
+ "Unknown state" : ltssm_str[ltssm_index];
+ dev_err(pcie->dev, "PCIe link down, current ltssm state: %s\n",
+ ltssm_state);
return err;
}
--
2.18.0
