On 3/14/2025 10:50 PM, Manivannan Sadhasivam wrote:
On Wed, Feb 26, 2025 at 06:36:00PM +0800, Wenbin Yao wrote:
From: Qiang Yu <quic_qianyu@xxxxxxxxxxx>
Some QCOM PCIe PHYs support no_csr reset. Unlike BCR reset which resets the
whole PHY (hardware and register), no_csr reset only resets PHY hardware
but retains register values, which means PHY setting can be skipped during
PHY init if PCIe link is enabled in booltloader and only no_csr is toggled
after that.
Hence, determine whether the PHY has been enabled in bootloader by
verifying QPHY_START_CTRL register. If it's programmed and no_csr reset is
available, skip BCR reset and PHY register setting to establish the PCIe
link with bootloader - programmed PHY settings.
Signed-off-by: Qiang Yu <quic_qianyu@xxxxxxxxxxx>
Signed-off-by: Wenbin Yao <quic_wenbyao@xxxxxxxxxxx>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
One nit below.
---
drivers/phy/qualcomm/phy-qcom-qmp-pcie.c | 69 ++++++++++++++++++++----
1 file changed, 59 insertions(+), 10 deletions(-)
diff --git a/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c b/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c
index 219266125cf2..c3642d1807e4 100644
--- a/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c
+++ b/drivers/phy/qualcomm/phy-qcom-qmp-pcie.c
@@ -2805,6 +2805,7 @@ struct qmp_pcie {
const struct qmp_phy_cfg *cfg;
bool tcsr_4ln_config;
+ bool skip_init;
void __iomem *serdes;
void __iomem *pcs;
@@ -3976,18 +3977,38 @@ static int qmp_pcie_init(struct phy *phy)
{
struct qmp_pcie *qmp = phy_get_drvdata(phy);
const struct qmp_phy_cfg *cfg = qmp->cfg;
+ void __iomem *pcs = qmp->pcs;
+ bool phy_initialized = !!(readl(pcs + cfg->regs[QPHY_START_CTRL]));
int ret;
+ qmp->skip_init = qmp->nocsr_reset && phy_initialized;
+ /*
+ * We need to check the existence of init sequences in two cases:
+ * 1. The PHY doesn't support no_csr reset.
+ * 2. The PHY supports no_csr reset but isn't initialized by bootloader.
+ * As we can't skip init in these two cases.
+ */
+ if (!qmp->skip_init && !cfg->tbls.serdes_num) {
+ dev_err(qmp->dev, "no init sequences are available\n");
"Init sequence not available\n"
+ return -EINVAL;
-ENODATA
Will fix in the next version.
- Mani
--
With best wishes
Wenbin
