| Message ID | 20220324072548.11408-1-jianjun.wang@mediatek.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | PCI: mediatek-gen3: Print LTSSM state when PCIe link down | expand |
Il 24/03/22 08:25, Jianjun Wang ha scritto: > 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@mediatek.com> Hello Jianjun, this patch is really helpful when comes to understand the source of an issue, so I agree with it - and thank you for that. Though, I think that you should still print the hex number along with the meaning of it, check below: > --- > 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 ..snip.. > @@ -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", There, I think that you should do: dev_err(pcie->dev, "PCIe link down, current LTSSM state: %s (%#x)\n", ltssm_state, val); this will be extremely useful in the "Unknown state" case. After fixing that, Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> Regards, Angelo
On Mon, 2022-03-28 at 16:39 +0200, AngeloGioacchino Del Regno wrote: > Il 24/03/22 08:25, Jianjun Wang ha scritto: > > 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@mediatek.com> > > Hello Jianjun, > this patch is really helpful when comes to understand the source of > an issue, > so I agree with it - and thank you for that. > > Though, I think that you should still print the hex number along with > the > meaning of it, check below: > > > --- > > 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 > > ..snip.. > > > @@ -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", > > There, I think that you should do: > > dev_err(pcie->dev, "PCIe link down, current LTSSM state: %s (%#x)\n", > ltssm_state, val); > > this will be extremely useful in the "Unknown state" case. > > After fixing that, > > Reviewed-by: AngeloGioacchino Del Regno < > angelogioacchino.delregno@collabora.com> Thanks! > > Regards, > Angelo
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; }
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@mediatek.com> --- drivers/pci/controller/pcie-mediatek-gen3.c | 40 ++++++++++++++++++++- 1 file changed, 39 insertions(+), 1 deletion(-)