[PATCH] mmc: sdhci-pci-gli: Enlarge ASPM L1 entry delay of GL9763E (v2)

From: Renius Chen
Date: Fri Jan 15 2021 - 00:48:47 EST


GL9763E enters ASPM L1 state after a very short idle in default,
even during a burst of request. So the R/W performance of GL9763E
is low with some platforms, which support ASPM mechanism, due to
entering ASPM L1 state very frequently in R/W process. Set the L1
entry delay bits in vendor-specific register to 0x3FF to enlarge
the idle period to 260us for improving the R/W performance
of GL9763E.

Signed-off-by: Renius Chen <reniuschengl@xxxxxxxxx>
---
drivers/mmc/host/sdhci-pci-gli.c | 10 ++++++++++
1 file changed, 10 insertions(+)

diff --git a/drivers/mmc/host/sdhci-pci-gli.c b/drivers/mmc/host/sdhci-pci-gli.c
index c6a107d7c742..fb14f70cb9a0 100644
--- a/drivers/mmc/host/sdhci-pci-gli.c
+++ b/drivers/mmc/host/sdhci-pci-gli.c
@@ -88,6 +88,10 @@
#define PCIE_GLI_9763E_SCR 0x8E0
#define GLI_9763E_SCR_AXI_REQ BIT(9)

+#define PCIE_GLI_9763E_CFG2 0x8A4
+#define GLI_9763E_CFG2_L1DLY GENMASK(28, 19)
+#define GLI_9763E_CFG2_L1DLY_MAX 0x3FF
+
#define PCIE_GLI_9763E_MMC_CTRL 0x960
#define GLI_9763E_HS400_SLOW BIT(3)

@@ -792,6 +796,12 @@ static void gli_set_gl9763e(struct sdhci_pci_slot *slot)
value &= ~GLI_9763E_HS400_SLOW;
pci_write_config_dword(pdev, PCIE_GLI_9763E_MMC_CTRL, value);

+ pci_read_config_dword(pdev, PCIE_GLI_9763E_CFG2, &value);
+ value &= ~GLI_9763E_CFG2_L1DLY;
+ /* set ASPM L1 entry delay to 260us */
+ value |= FIELD_PREP(GLI_9763E_CFG2_L1DLY, GLI_9763E_CFG2_L1DLY_MAX);
+ pci_write_config_dword(pdev, PCIE_GLI_9763E_CFG2, value);
+
pci_read_config_dword(pdev, PCIE_GLI_9763E_VHS, &value);
value &= ~GLI_9763E_VHS_REV;
value |= FIELD_PREP(GLI_9763E_VHS_REV, GLI_9763E_VHS_REV_R);
--
2.27.0