[RESEND, PATCH] mmc: sdhci-pci-gli: Improve GL9763E L1 entry delay to increase battery life

From: Ben Chuang
Date: Wed Apr 07 2021 - 05:35:25 EST


From: Ben Chuang <ben.chuang@xxxxxxxxxxxxxxxxxxx>

For GL9763E, although there is the best performance at the maximum delay.
Change the value to 20us in order to have better power consumption.
This change may reduce the maximum performance by 10%.

Signed-off-by: Ben Chuang <ben.chuang@xxxxxxxxxxxxxxxxxxx>
---
drivers/mmc/host/sdhci-pci-gli.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/mmc/host/sdhci-pci-gli.c b/drivers/mmc/host/sdhci-pci-gli.c
index 4a0f69b97a78..3b0a049d4124 100644
--- a/drivers/mmc/host/sdhci-pci-gli.c
+++ b/drivers/mmc/host/sdhci-pci-gli.c
@@ -90,7 +90,7 @@

#define PCIE_GLI_9763E_CFG2 0x8A4
#define GLI_9763E_CFG2_L1DLY GENMASK(28, 19)
-#define GLI_9763E_CFG2_L1DLY_MAX 0x3FF
+#define GLI_9763E_CFG2_L1DLY_MID 0x50

#define PCIE_GLI_9763E_MMC_CTRL 0x960
#define GLI_9763E_HS400_SLOW BIT(3)
@@ -802,8 +802,8 @@ static void gli_set_gl9763e(struct sdhci_pci_slot *slot)

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);
+ /* set ASPM L1 entry delay to 20us */
+ value |= FIELD_PREP(GLI_9763E_CFG2_L1DLY, GLI_9763E_CFG2_L1DLY_MID);
pci_write_config_dword(pdev, PCIE_GLI_9763E_CFG2, value);

pci_read_config_dword(pdev, PCIE_GLI_9763E_CLKRXDLY, &value);
--
2.30.0