From 36ed2fd32b2cf7ff49804fae455e58e4d3b3bcad Mon Sep 17 00:00:00 2001 From: Ben Chuang Date: Thu, 14 Apr 2022 17:49:45 +0800 Subject: [PATCH] mmc: sdhci-pci-gli: A workaround to allow GL9755 to enter ASPM L1.2 When GL9755 enters ASPM L1 sub-states, it will stay at L1.1 and will not enter L1.2. The workaround is to toggle PM state to allow GL9755 to enter ASPM L1.2. Signed-off-by: Ben Chuang Acked-by: Adrian Hunter Link: https://lore.kernel.org/r/20220414094945.457500-1-benchuanggli@gmail.com Signed-off-by: Ulf Hansson --- 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 d09728c..1499a64 100644 --- a/drivers/mmc/host/sdhci-pci-gli.c +++ b/drivers/mmc/host/sdhci-pci-gli.c @@ -142,6 +142,9 @@ #define PCI_GLI_9755_MISC 0x78 #define PCI_GLI_9755_MISC_SSC_OFF BIT(26) +#define PCI_GLI_9755_PM_CTRL 0xFC +#define PCI_GLI_9755_PM_STATE GENMASK(1, 0) + #define GLI_MAX_TUNING_LOOP 40 /* Genesys Logic chipset */ @@ -676,6 +679,13 @@ static void gl9755_hw_setting(struct sdhci_pci_slot *slot) GLI_9755_CFG2_L1DLY_VALUE); pci_write_config_dword(pdev, PCI_GLI_9755_CFG2, value); + /* toggle PM state to allow GL9755 to enter ASPM L1.2 */ + pci_read_config_dword(pdev, PCI_GLI_9755_PM_CTRL, &value); + value |= PCI_GLI_9755_PM_STATE; + pci_write_config_dword(pdev, PCI_GLI_9755_PM_CTRL, value); + value &= ~PCI_GLI_9755_PM_STATE; + pci_write_config_dword(pdev, PCI_GLI_9755_PM_CTRL, value); + gl9755_wt_off(pdev); } -- 2.7.4