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>
This commit is contained in:
Richard Zhu 2013-10-15 10:44:54 +08:00 committed by Tejun Heo
parent 89951f2245
commit 8b789d8981
4 changed files with 105 additions and 5 deletions

View File

@ -339,6 +339,7 @@ extern struct device_attribute *ahci_sdev_attrs[];
.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_hw_interrupt(int irq, void *dev_instance);
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)

View File

@ -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 imx_ahci_priv {
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 @@ 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 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 @@ static int imx_ahci_probe(struct platform_device *pdev)
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");

View File

@ -49,10 +49,11 @@ static struct platform_device_id ahci_devtype[] = {
};
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,

View File

@ -89,7 +89,6 @@ static int ahci_pmp_retry_softreset(struct ata_link *link, unsigned int *class,
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 @@ static void ahci_thaw(struct ata_port *ap)
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 @@ static void ahci_error_handler(struct ata_port *ap)
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)
{