MLK-16799-2: mtd: flexspi: support runtime pm for flexspi

enabled runtime pm for flexspi, also removed the redundant clock.
Tested with the latest SCFW and ATF.

BuildInfo:
	- SCFW 15d20cde, IMX-MKIMAGE ff9860c5, ATF
	- U-Boot 2017.03-00003-gd09f5db

Signed-off-by: Han Xu <han.xu@nxp.com>

diff --git a/drivers/mtd/spi-nor/fsl-flexspi.c b/drivers/mtd/spi-nor/fsl-flexspi.c
index d4f122b..1e8f2e4 100644 (file)
--- a/drivers/mtd/spi-nor/fsl-flexspi.c
+++ b/drivers/mtd/spi-nor/fsl-flexspi.c
@@ -30,6 +30,10 @@
 #include <linux/pm_qos.h>
 #include <linux/pci.h>
 #include <soc/imx8/sc/sci.h>
+#include <linux/pm_runtime.h>
+
+/* runtime pm timeout */
+#define FSL_FLEXSPI_RPM_TIMEOUT 50 /* 50ms */
 
 /* The registers */
 #define FLEXSPI_MCR0                   0x00
@@ -443,7 +447,7 @@ struct fsl_flexspi {
        u32 memmap_phy;
        u32 memmap_offs;
        u32 memmap_len;
-       struct clk *clk, *clk_en;
+       struct clk *clk;
        struct device *dev;
        struct completion c;
        struct fsl_flexspi_devtype_data *devtype_data;
@@ -893,13 +897,9 @@ static int fsl_flexspi_clk_prep_enable(struct fsl_flexspi *flex)
 {
        int ret;
 
-       ret = clk_prepare_enable(flex->clk_en);
-       if (ret)
-               return ret;
-
        ret = clk_prepare_enable(flex->clk);
        if (ret) {
-               clk_disable_unprepare(flex->clk_en);
+               dev_err(flex->dev, "failed to enable the clock\n");
                return ret;
        }
 
@@ -910,7 +910,17 @@ static int fsl_flexspi_clk_prep_enable(struct fsl_flexspi *flex)
 static void fsl_flexspi_clk_disable_unprep(struct fsl_flexspi *flex)
 {
        clk_disable_unprepare(flex->clk);
-       clk_disable_unprepare(flex->clk_en);
+}
+
+static int fsl_flexspi_init_rpm(struct fsl_flexspi *flex)
+{
+       struct device *dev = flex->dev;
+
+       pm_runtime_enable(dev);
+       pm_runtime_set_autosuspend_delay(dev, FSL_FLEXSPI_RPM_TIMEOUT);
+       pm_runtime_use_autosuspend(dev);
+
+       return 0;
 }
 
 /* We use this function to do some basic init for spi_nor_scan(). */
@@ -918,6 +928,13 @@ static int fsl_flexspi_nor_setup(struct fsl_flexspi *flex)
 {
        void __iomem *base = flex->iobase;
        u32 reg;
+       int ret;
+
+       ret = pm_runtime_get_sync(flex->dev);
+       if (ret < 0) {
+               dev_err(flex->dev, "Failed to enable clock %d\n", __LINE__);
+               return ret;
+       }
 
        /* Reset the module */
        writel(FLEXSPI_MCR0_SWRST_MASK, base + FLEXSPI_MCR0);
@@ -940,6 +957,10 @@ static int fsl_flexspi_nor_setup(struct fsl_flexspi *flex)
 
        /* enable the interrupt */
        writel(FLEXSPI_INTEN_IPCMDDONE_MASK, flex->iobase + FLEXSPI_INTEN);
+
+       pm_runtime_mark_last_busy(flex->dev);
+       pm_runtime_put_autosuspend(flex->dev);
+
        return 0;
 }
 
@@ -948,6 +969,12 @@ static int fsl_flexspi_nor_setup_last(struct fsl_flexspi *flex)
        unsigned long rate = flex->clk_rate;
        int ret;
 
+       ret = pm_runtime_get_sync(flex->dev);
+       if (ret < 0) {
+               dev_err(flex->dev, "Failed to enable clock %d\n", __LINE__);
+               return ret;
+       }
+
        /* disable and unprepare clock to avoid glitch pass to controller */
        fsl_flexspi_clk_disable_unprep(flex);
 
@@ -965,6 +992,9 @@ static int fsl_flexspi_nor_setup_last(struct fsl_flexspi *flex)
        /* Init for AHB read */
        fsl_flexspi_init_ahb_read(flex);
 
+       pm_runtime_mark_last_busy(flex->dev);
+       pm_runtime_put_autosuspend(flex->dev);
+
        return 0;
 }
 
@@ -1104,9 +1134,11 @@ static int fsl_flexspi_prep(struct spi_nor *nor, enum spi_nor_ops ops)
 
        mutex_lock(&flex->lock);
 
-       ret = fsl_flexspi_clk_prep_enable(flex);
-       if (ret)
+       ret = pm_runtime_get_sync(flex->dev);
+       if (ret < 0) {
+               dev_err(flex->dev, "Failed to enable clock %d\n", __LINE__);
                goto err_mutex;
+       }
 
        fsl_flexspi_set_base_addr(flex, nor);
        return 0;
@@ -1120,7 +1152,8 @@ static void fsl_flexspi_unprep(struct spi_nor *nor, enum spi_nor_ops ops)
 {
        struct fsl_flexspi *flex = nor->priv;
 
-       fsl_flexspi_clk_disable_unprep(flex);
+       pm_runtime_mark_last_busy(flex->dev);
+       pm_runtime_put_autosuspend(flex->dev);
        mutex_unlock(&flex->lock);
 }
 
@@ -1155,6 +1188,7 @@ static int fsl_flexspi_probe(struct platform_device *pdev)
        flex->dev = dev;
        flex->devtype_data = (struct fsl_flexspi_devtype_data *)of_id->data;
        platform_set_drvdata(pdev, flex);
+       dev_set_drvdata(dev, flex);
 
        /* find the resources */
        res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "FlexSPI");
@@ -1184,11 +1218,7 @@ static int fsl_flexspi_probe(struct platform_device *pdev)
        flex->memmap_phy = res->start;
 
        /* find the clocks */
-       flex->clk_en = devm_clk_get(dev, "qspi_en");
-       if (IS_ERR(flex->clk_en))
-               return PTR_ERR(flex->clk_en);
-
-       flex->clk = devm_clk_get(dev, "qspi");
+       flex->clk = devm_clk_get(dev, "fspi");
        if (IS_ERR(flex->clk))
                return PTR_ERR(flex->clk);
 
@@ -1198,7 +1228,8 @@ static int fsl_flexspi_probe(struct platform_device *pdev)
        if (ret)
                flex->ddr_smp = 0;
 
-       ret = fsl_flexspi_clk_prep_enable(flex);
+       /* enable the clock */
+       ret = fsl_flexspi_init_rpm(flex);
        if (ret) {
                dev_err(dev, "can not enable the clock\n");
                goto clk_failed;
@@ -1208,19 +1239,19 @@ static int fsl_flexspi_probe(struct platform_device *pdev)
        ret = platform_get_irq(pdev, 0);
        if (ret < 0) {
                dev_err(dev, "failed to get the irq: %d\n", ret);
-               goto irq_failed;
+               goto clk_failed;
        }
 
        ret = devm_request_irq(dev, ret,
                        fsl_flexspi_irq_handler, 0, pdev->name, flex);
        if (ret) {
                dev_err(dev, "failed to request irq: %d\n", ret);
-               goto irq_failed;
+               goto clk_failed;
        }
 
        ret = fsl_flexspi_nor_setup(flex);
        if (ret)
-               goto irq_failed;
+               goto clk_failed;
 
        if (of_get_property(np, "fsl,qspi-has-second-chip", NULL))
                flex->has_second_chip = true;
@@ -1304,7 +1335,6 @@ static int fsl_flexspi_probe(struct platform_device *pdev)
        if (ret)
                goto last_init_failed;
 
-       fsl_flexspi_clk_disable_unprep(flex);
        return 0;
 
 last_init_failed:
@@ -1316,8 +1346,6 @@ last_init_failed:
        }
 mutex_failed:
        mutex_destroy(&flex->lock);
-irq_failed:
-       fsl_flexspi_clk_disable_unprep(flex);
 clk_failed:
        dev_err(dev, "Freescale FlexSPI probe failed\n");
        return ret;
@@ -1338,6 +1366,8 @@ static int fsl_flexspi_remove(struct platform_device *pdev)
        /* disable the hardware */
        writel(FLEXSPI_MCR0_MDIS_MASK, flex->iobase + FLEXSPI_MCR0);
 
+       pm_runtime_disable(flex->dev);
+
        mutex_destroy(&flex->lock);
 
        if (flex->ahb_addr)
@@ -1346,26 +1376,48 @@ static int fsl_flexspi_remove(struct platform_device *pdev)
        return 0;
 }
 
-static int fsl_flexspi_suspend(struct platform_device *pdev, pm_message_t state)
+#ifdef CONFIG_PM_SLEEP
+static int fsl_flexspi_pm_suspend(struct device *dev)
 {
-       return 0;
+       return pm_runtime_force_suspend(dev);
 }
 
-static int fsl_flexspi_resume(struct platform_device *pdev)
+static int fsl_flexspi_pm_resume(struct device *dev)
 {
+       return pm_runtime_force_resume(dev);
+}
+#endif
+
+int fsl_flexspi_runtime_suspend(struct device *dev)
+{
+       struct fsl_flexspi *flex = dev_get_drvdata(dev);
+
+       fsl_flexspi_clk_disable_unprep(flex);
+
        return 0;
 }
 
+int fsl_flexspi_runtime_resume(struct device *dev)
+{
+       struct fsl_flexspi *flex = dev_get_drvdata(dev);
+
+       return fsl_flexspi_clk_prep_enable(flex);
+}
+
+static const struct dev_pm_ops fsl_flexspi_pm_ops = {
+       SET_RUNTIME_PM_OPS(fsl_flexspi_runtime_suspend, fsl_flexspi_runtime_resume, NULL)
+       SET_SYSTEM_SLEEP_PM_OPS(fsl_flexspi_pm_suspend, fsl_flexspi_pm_resume)
+};
+
 static struct platform_driver fsl_flexspi_driver = {
        .driver = {
                .name   = "fsl-flexspi",
                .bus    = &platform_bus_type,
+               .pm     = &fsl_flexspi_pm_ops,
                .of_match_table = fsl_flexspi_dt_ids,
        },
        .probe          = fsl_flexspi_probe,
        .remove         = fsl_flexspi_remove,
-       .suspend        = fsl_flexspi_suspend,
-       .resume         = fsl_flexspi_resume,
 };
 module_platform_driver(fsl_flexspi_driver);