ahci: imx: setup power saving methods
In order to save power consumption as much as possible.
* Disable sata phy internal pll reference clock when sysetem enter
into suspend mode, enable it after resume.
* Setup module parameter used to enable imx ahci test power down
mode(PDDQ) or not, when there is no device detected on the port
* minor modifications:
- The format of the copyright is changed, because that the original
one can't pass fsl internal patch reivew without the character
'(c)'.
- Exports ahci_platform_ops and ahci_error_handler().
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.hotplug=1" into kernel command line if your don't
want to enable PDDQ mode when no device detected on the port.
tj: Slightly updated description and comments.
Signed-off-by: Richard Zhu <r65037@freescale.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
diff --git a/drivers/ata/ahci.h b/drivers/ata/ahci.h
index 1145637..2289efd 100644
--- a/drivers/ata/ahci.h
+++ b/drivers/ata/ahci.h
@@ -339,6 +339,7 @@
.sdev_attrs = ahci_sdev_attrs
extern struct ata_port_operations ahci_ops;
+extern struct ata_port_operations ahci_platform_ops;
extern struct ata_port_operations ahci_pmp_retry_srst_ops;
unsigned int ahci_dev_classify(struct ata_port *ap);
@@ -368,6 +369,7 @@
irqreturn_t ahci_thread_fn(int irq, void *dev_instance);
void ahci_print_info(struct ata_host *host, const char *scc_s);
int ahci_host_activate(struct ata_host *host, int irq, unsigned int n_msis);
+void ahci_error_handler(struct ata_port *ap);
static inline void __iomem *__ahci_port_base(struct ata_host *host,
unsigned int port_no)
diff --git a/drivers/ata/ahci_imx.c b/drivers/ata/ahci_imx.c
index 58debb0..ae2d73f 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
*
@@ -25,10 +25,13 @@
#include <linux/of_device.h>
#include <linux/mfd/syscon.h>
#include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
+#include <linux/libata.h>
#include "ahci.h"
enum {
- HOST_TIMER1MS = 0xe0, /* Timer 1-ms */
+ PORT_PHY_CTL = 0x178, /* Port0 PHY Control */
+ PORT_PHY_CTL_PDDQ_LOC = 0x100000, /* PORT_PHY_CTL bits */
+ HOST_TIMER1MS = 0xe0, /* Timer 1-ms */
};
struct imx_ahci_priv {
@@ -36,6 +39,56 @@
struct clk *sata_ref_clk;
struct clk *ahb_clk;
struct regmap *gpr;
+ bool no_device;
+ bool first_time;
+};
+
+static int ahci_imx_hotplug;
+module_param_named(hotplug, ahci_imx_hotplug, int, 0644);
+MODULE_PARM_DESC(hotplug, "AHCI IMX hot-plug support (0=Don't support, 1=support)");
+
+static void ahci_imx_error_handler(struct ata_port *ap)
+{
+ u32 reg_val;
+ struct ata_device *dev;
+ struct ata_host *host = dev_get_drvdata(ap->dev);
+ struct ahci_host_priv *hpriv = host->private_data;
+ void __iomem *mmio = hpriv->mmio;
+ struct imx_ahci_priv *imxpriv = dev_get_drvdata(ap->dev->parent);
+
+ ahci_error_handler(ap);
+
+ if (!(imxpriv->first_time) || ahci_imx_hotplug)
+ return;
+
+ imxpriv->first_time = false;
+
+ ata_for_each_dev(dev, &ap->link, ENABLED)
+ return;
+ /*
+ * Disable link to save power. An imx ahci port can't be recovered
+ * without full reset once the pddq mode is enabled making it
+ * impossible to use as part of libata LPM.
+ */
+ 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 = true;
+}
+
+static struct ata_port_operations ahci_imx_ops = {
+ .inherits = &ahci_platform_ops,
+ .error_handler = ahci_imx_error_handler,
+};
+
+static const struct ata_port_info ahci_imx_port_info = {
+ .flags = AHCI_FLAG_COMMON,
+ .pio_mask = ATA_PIO4,
+ .udma_mask = ATA_UDMA6,
+ .port_ops = &ahci_imx_ops,
};
static int imx6q_sata_init(struct device *dev, void __iomem *mmio)
@@ -117,9 +170,51 @@
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 no_device is set, The CLKs had been gated off in the
+ * initialization so don't do it again here.
+ */
+ 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,
+ .ata_port_info = &ahci_imx_port_info,
+ .suspend = imx_ahci_suspend,
+ .resume = imx_ahci_resume,
};
static const struct of_device_id imx_ahci_of_match[] = {
@@ -152,6 +247,8 @@
ahci_dev = &ahci_pdev->dev;
ahci_dev->parent = dev;
+ imxpriv->no_device = false;
+ imxpriv->first_time = true;
imxpriv->ahb_clk = devm_clk_get(dev, "ahb");
if (IS_ERR(imxpriv->ahb_clk)) {
dev_err(dev, "can't get ahb clock.\n");
diff --git a/drivers/ata/ahci_platform.c b/drivers/ata/ahci_platform.c
index 2daaee0..7708ca7 100644
--- a/drivers/ata/ahci_platform.c
+++ b/drivers/ata/ahci_platform.c
@@ -49,10 +49,11 @@
};
MODULE_DEVICE_TABLE(platform, ahci_devtype);
-static struct ata_port_operations ahci_platform_ops = {
+struct ata_port_operations ahci_platform_ops = {
.inherits = &ahci_ops,
.host_stop = ahci_host_stop,
};
+EXPORT_SYMBOL_GPL(ahci_platform_ops);
static struct ata_port_operations ahci_platform_retry_srst_ops = {
.inherits = &ahci_pmp_retry_srst_ops,
diff --git a/drivers/ata/libahci.c b/drivers/ata/libahci.c
index b67086f..7e2a1b3 100644
--- a/drivers/ata/libahci.c
+++ b/drivers/ata/libahci.c
@@ -89,7 +89,6 @@
static int ahci_hardreset(struct ata_link *link, unsigned int *class,
unsigned long deadline);
static void ahci_postreset(struct ata_link *link, unsigned int *class);
-static void ahci_error_handler(struct ata_port *ap);
static void ahci_post_internal_cmd(struct ata_queued_cmd *qc);
static void ahci_dev_config(struct ata_device *dev);
#ifdef CONFIG_PM
@@ -1982,7 +1981,7 @@
writel(pp->intr_mask, port_mmio + PORT_IRQ_MASK);
}
-static void ahci_error_handler(struct ata_port *ap)
+void ahci_error_handler(struct ata_port *ap)
{
if (!(ap->pflags & ATA_PFLAG_FROZEN)) {
/* restart engine */
@@ -1995,6 +1994,7 @@
if (!ata_dev_enabled(ap->link.device))
ahci_stop_engine(ap);
}
+EXPORT_SYMBOL_GPL(ahci_error_handler);
static void ahci_post_internal_cmd(struct ata_queued_cmd *qc)
{