From: Richard Zhu <r65037@xxxxxxxxxxxxx>
In order to save power consumption amap.
* Disable sata phy internal pll reference clock when
sysetem enter into suspend mode, enable it after resume.
* Enter into test power down mode when there is no sata disk
detected on the port and 'AHCI_IMX_PHY_POWER_DOWN_MODE' is
enabled.
Signed-off-by: Richard Zhu <r65037@xxxxxxxxxxxxx>
---
drivers/ata/Kconfig | 8 +++++
drivers/ata/ahci_imx.c | 78 ++++++++++++++++++++++++++++++++++++++++++++++--
2 files changed, 83 insertions(+), 3 deletions(-)
diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig
index 4e73772..84b09f0 100644
--- a/drivers/ata/Kconfig
+++ b/drivers/ata/Kconfig
@@ -106,6 +106,14 @@ config AHCI_IMX
If unsure, say N.
+config AHCI_IMX_PHY_POWER_DOWN_MODE
+ bool "Power saving mode when there is no SATA DEV detected on the port"
+ depends on AHCI_IMX
+ help
+ This option enable the power down mode of the imx ahci when there is
+ no sata device detected on the port, the sata port wouldn't be
+ functional anymore except one system power down, and power up again.
+
config SATA_FSL
tristate "Freescale 3.0Gbps SATA support"
depends on FSL_SOC
diff --git a/drivers/ata/ahci_imx.c b/drivers/ata/ahci_imx.c
index 58debb0..c15dade 100644
--- a/drivers/ata/ahci_imx.c
+++ b/drivers/ata/ahci_imx.c
@@ -1,6 +1,6 @@
/*
+ * copyright (c) 2013 Freescale Semiconductor, Inc.
* Freescale IMX AHCI SATA platform driver
- * Copyright 2013 Freescale Semiconductor, Inc.
*
* based on the AHCI SATA platform driver by Jeff Garzik and Anton Vorontsov
*
@@ -28,6 +28,10 @@
#include "ahci.h"
enum {
+ /* Port0 PHY Control */
+ PORT_PHY_CTL = 0x178,
+ /* PORT_PHY_CTL bits */
+ PORT_PHY_CTL_PDDQ_LOC = 0x100000,
HOST_TIMER1MS = 0xe0, /* Timer 1-ms */
};
@@ -36,12 +40,13 @@ struct imx_ahci_priv {
struct clk *sata_ref_clk;
struct clk *ahb_clk;
struct regmap *gpr;
+ bool no_device;
};
static int imx6q_sata_init(struct device *dev, void __iomem *mmio)
{
- int ret = 0;
- unsigned int reg_val;
+ int ret = 0, iterations = 200;
+ u32 reg_val, sstatus;
struct imx_ahci_priv *imxpriv = dev_get_drvdata(dev->parent);
imxpriv->gpr =
@@ -105,6 +110,36 @@ static int imx6q_sata_init(struct device *dev, void __iomem *mmio)
reg_val = clk_get_rate(imxpriv->ahb_clk) / 1000;
writel(reg_val, mmio + HOST_TIMER1MS);
+ if (IS_ENABLED(CONFIG_AHCI_IMX_PHY_POWER_DOWN_MODE)) {
+ /*
+ * In order to save power consumption, enter PDDQ mode
+ * when there is no device detected on the port
+ */
+ do {
+ sstatus = readl(mmio + 0x100 + PORT_SCR_STAT);
+ if ((sstatus & 0xF) == 0)
+ usleep_range(1000, 2000);
+ else
+ break;
+
+ if (iterations == 0) {
+ pr_info("No sata disk.\n");
+ reg_val = readl(mmio + PORT_PHY_CTL);
+ writel(reg_val | PORT_PHY_CTL_PDDQ_LOC,
+ mmio + PORT_PHY_CTL);
+ regmap_update_bits(imxpriv->gpr, IOMUXC_GPR13,
+ IMX6Q_GPR13_SATA_MPLL_CLK_EN,
+ !IMX6Q_GPR13_SATA_MPLL_CLK_EN);
+ clk_disable_unprepare(imxpriv->sata_ref_clk);
+ imxpriv->no_device = 1;
+
+ return 0;
+ }
+ } while (iterations-- > 0);
+ } else {
+ imxpriv->no_device = 0;
+ }
+
return 0;
}
@@ -117,9 +152,46 @@ static void imx6q_sata_exit(struct device *dev)
clk_disable_unprepare(imxpriv->sata_ref_clk);
}
+static int imx_ahci_suspend(struct device *dev)
+{
+ struct imx_ahci_priv *imxpriv = dev_get_drvdata(dev->parent);
+
+ if (!(imxpriv->no_device)) {
+ regmap_update_bits(imxpriv->gpr, IOMUXC_GPR13,
+ IMX6Q_GPR13_SATA_MPLL_CLK_EN,
+ !IMX6Q_GPR13_SATA_MPLL_CLK_EN);
+ clk_disable_unprepare(imxpriv->sata_ref_clk);
+ }
+
+ return 0;
+}
+
+static int imx_ahci_resume(struct device *dev)
+{
+ struct imx_ahci_priv *imxpriv = dev_get_drvdata(dev->parent);
+ int ret;
+
+ if (!(imxpriv->no_device)) {
+ ret = clk_prepare_enable(imxpriv->sata_ref_clk);
+ if (ret < 0) {
+ dev_err(dev, "pre-enable sata_ref clock err:%d\n", ret);
+ return ret;
+ }
+
+ regmap_update_bits(imxpriv->gpr, IOMUXC_GPR13,
+ IMX6Q_GPR13_SATA_MPLL_CLK_EN,
+ IMX6Q_GPR13_SATA_MPLL_CLK_EN);
+ usleep_range(1000, 2000);
+ }
+
+ return 0;
+}
+
static struct ahci_platform_data imx6q_sata_pdata = {
.init = imx6q_sata_init,
.exit = imx6q_sata_exit,
+ .suspend = imx_ahci_suspend,
+ .resume = imx_ahci_resume,
};
static const struct of_device_id imx_ahci_of_match[] = {
--
1.7.5.4
--
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