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From:   Renius Chen <reniuschengl@gmail.com>
To:     ulf.hansson@linaro.org, adrian.hunter@intel.com
Cc:     linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org,
        ben.chuang@genesyslogic.com.tw, greg.tu@genesyslogic.com.tw,
        Renius Chen <reniuschengl@gmail.com>
Subject: [PATCH] mmc: sdhci-pci-gli: Enlarge ASPM L1 entry delay of GL9763E (v2)
Date:   Fri, 15 Jan 2021 13:47:36 +0800
Message-Id: <20210115054736.27769-1-reniuschengl@gmail.com>
MIME-Version: 1.0
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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@gmail.com>
---
 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