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Diffstat (limited to 'arch/arm/mach-davinci/aemif.c')
-rw-r--r--arch/arm/mach-davinci/aemif.c107
1 files changed, 96 insertions, 11 deletions
diff --git a/arch/arm/mach-davinci/aemif.c b/arch/arm/mach-davinci/aemif.c
index f091a9010c2f..ff8b7e76b6e9 100644
--- a/arch/arm/mach-davinci/aemif.c
+++ b/arch/arm/mach-davinci/aemif.c
@@ -16,6 +16,7 @@
#include <linux/time.h>
#include <linux/platform_data/mtd-davinci-aemif.h>
+#include <linux/platform_data/mtd-davinci.h>
/* Timing value configuration */
@@ -43,6 +44,17 @@
WSTROBE(WSTROBE_MAX) | \
WSETUP(WSETUP_MAX))
+static inline unsigned int davinci_aemif_readl(void __iomem *base, int offset)
+{
+ return readl_relaxed(base + offset);
+}
+
+static inline void davinci_aemif_writel(void __iomem *base,
+ int offset, unsigned long value)
+{
+ writel_relaxed(value, base + offset);
+}
+
/*
* aemif_calc_rate - calculate timing data.
* @wanted: The cycle time needed in nanoseconds.
@@ -76,6 +88,7 @@ static int aemif_calc_rate(int wanted, unsigned long clk, int max)
* @t: timing values to be progammed
* @base: The virtual base address of the AEMIF interface
* @cs: chip-select to program the timing values for
+ * @clkrate: the AEMIF clkrate
*
* This function programs the given timing values (in real clock) into the
* AEMIF registers taking the AEMIF clock into account.
@@ -86,24 +99,17 @@ static int aemif_calc_rate(int wanted, unsigned long clk, int max)
*
* Returns 0 on success, else negative errno.
*/
-int davinci_aemif_setup_timing(struct davinci_aemif_timing *t,
- void __iomem *base, unsigned cs)
+static int davinci_aemif_setup_timing(struct davinci_aemif_timing *t,
+ void __iomem *base, unsigned cs,
+ unsigned long clkrate)
{
unsigned set, val;
int ta, rhold, rstrobe, rsetup, whold, wstrobe, wsetup;
unsigned offset = A1CR_OFFSET + cs * 4;
- struct clk *aemif_clk;
- unsigned long clkrate;
if (!t)
return 0; /* Nothing to do */
- aemif_clk = clk_get(NULL, "aemif");
- if (IS_ERR(aemif_clk))
- return PTR_ERR(aemif_clk);
-
- clkrate = clk_get_rate(aemif_clk);
-
clkrate /= 1000; /* turn clock into kHz for ease of use */
ta = aemif_calc_rate(t->ta, clkrate, TA_MAX);
@@ -130,4 +136,83 @@ int davinci_aemif_setup_timing(struct davinci_aemif_timing *t,
return 0;
}
-EXPORT_SYMBOL(davinci_aemif_setup_timing);
+
+/**
+ * davinci_aemif_setup - setup AEMIF interface by davinci_nand_pdata
+ * @pdev - link to platform device to setup settings for
+ *
+ * This function does not use any locking while programming the AEMIF
+ * because it is expected that there is only one user of a given
+ * chip-select.
+ *
+ * Returns 0 on success, else negative errno.
+ */
+int davinci_aemif_setup(struct platform_device *pdev)
+{
+ struct davinci_nand_pdata *pdata = dev_get_platdata(&pdev->dev);
+ uint32_t val;
+ unsigned long clkrate;
+ struct resource *res;
+ void __iomem *base;
+ struct clk *clk;
+ int ret = 0;
+
+ clk = clk_get(&pdev->dev, "aemif");
+ if (IS_ERR(clk)) {
+ ret = PTR_ERR(clk);
+ dev_dbg(&pdev->dev, "unable to get AEMIF clock, err %d\n", ret);
+ return ret;
+ }
+
+ ret = clk_prepare_enable(clk);
+ if (ret < 0) {
+ dev_dbg(&pdev->dev, "unable to enable AEMIF clock, err %d\n",
+ ret);
+ goto err_put;
+ }
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ if (!res) {
+ dev_err(&pdev->dev, "cannot get IORESOURCE_MEM\n");
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ base = ioremap(res->start, resource_size(res));
+ if (!base) {
+ dev_err(&pdev->dev, "ioremap failed for resource %pR\n", res);
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ /*
+ * Setup Async configuration register in case we did not boot
+ * from NAND and so bootloader did not bother to set it up.
+ */
+ val = davinci_aemif_readl(base, A1CR_OFFSET + pdev->id * 4);
+ /*
+ * Extended Wait is not valid and Select Strobe mode is not
+ * used
+ */
+ val &= ~(ACR_ASIZE_MASK | ACR_EW_MASK | ACR_SS_MASK);
+ if (pdata->options & NAND_BUSWIDTH_16)
+ val |= 0x1;
+
+ davinci_aemif_writel(base, A1CR_OFFSET + pdev->id * 4, val);
+
+ clkrate = clk_get_rate(clk);
+
+ if (pdata->timing)
+ ret = davinci_aemif_setup_timing(pdata->timing, base, pdev->id,
+ clkrate);
+
+ if (ret < 0)
+ dev_dbg(&pdev->dev, "NAND timing values setup fail\n");
+
+ iounmap(base);
+err:
+ clk_disable_unprepare(clk);
+err_put:
+ clk_put(clk);
+ return ret;
+}