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.
* Don't support hot-plug feature, and enter into test power
down mode(PDDQ) when there is no device detected on the port.
NOTE:
- The hot-plug can't be supported when PDDQ mode is
ever enabled.
- module parameter usage how-to:
* default: enable PDDQ mode when no device detected.
* add "ahci-imx.hp=1" into kernel command line if
your don't want to enable PDDQ mode when no device
detected on the port.
Signed-off-by: Richard Zhu <r65037@xxxxxxxxxxxxx>
---
drivers/ata/ahci_imx.c | 85 ++++++++++++++++++++++++++++++++++++++++++++++--
1 files changed, 82 insertions(+), 3 deletions(-)
diff --git a/drivers/ata/ahci_imx.c b/drivers/ata/ahci_imx.c
index 58debb0..8c2dc1a 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 +40,17 @@ struct imx_ahci_priv {
struct clk *sata_ref_clk;
struct clk *ahb_clk;
struct regmap *gpr;
+ bool no_device;
};
+static int ahci_imx_hp;
+module_param_named(hp, ahci_imx_hp, int, 0644);
+MODULE_PARM_DESC(hp, "AHCI IMX hot-plug support (0=Don't support, 1=support)");
+
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 +114,39 @@ 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 (ahci_imx_hp == 0) {
+ /*
+ * hot-plug is not supported.
+ * In order to save power consumption, enter PDDQ mode
+ * when there is no device detected on the port.
+ * NOTE: hot-plug wouldn't supported when PDDQ mode is
+ * ever entered.
+ */
+ 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 +159,46 @@ 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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