The BRCM NAND controller on NS2 SoC requires a reset to
cleanup previously configured NAND controller state.
This patch adds optional boolean device tree flag named
"brcm,nand-iproc-reset". If this flag is present in NAND
controller DT node then BRCM IPROC NAND driver will reset
the NAND controller before any commands are issued.
Signed-off-by: Anup Patel <anup.patel@xxxxxxxxxxxx>
Reviewed-by: Pramod KUMAR <pramodku@xxxxxxxxxxxx>
Reviewed-by: Ray Jui <rjui@xxxxxxxxxxxx>
Reviewed-by: Scott Branden <sbranden@xxxxxxxxxxxx>
---
drivers/mtd/nand/brcmnand/iproc_nand.c | 19 +++++++++++++++++++
1 file changed, 19 insertions(+)
diff --git a/drivers/mtd/nand/brcmnand/iproc_nand.c b/drivers/mtd/nand/brcmnand/iproc_nand.c
index 683495c..d837207 100644
--- a/drivers/mtd/nand/brcmnand/iproc_nand.c
+++ b/drivers/mtd/nand/brcmnand/iproc_nand.c
@@ -11,6 +11,7 @@
* GNU General Public License for more details.
*/
+#include <linux/delay.h>
#include <linux/device.h>
#include <linux/io.h>
#include <linux/ioport.h>
@@ -35,6 +36,10 @@ struct iproc_nand_soc_priv {
#define IPROC_NAND_APB_LE_MODE BIT(24)
#define IPROC_NAND_INT_CTRL_READ_ENABLE BIT(6)
+#define IPROC_NAND_RESET_OFFSET 0x3f8
+#define IPROC_NAND_RESET_BIT_SHIFT 0
+#define IPROC_NAND_RESET_BIT BIT(IPROC_NAND_RESET_BIT_SHIFT)
+
static bool iproc_nand_intc_ack(struct brcmnand_soc *soc)
{
struct iproc_nand_soc_priv *priv = soc->priv;
@@ -93,6 +98,7 @@ static void iproc_nand_apb_access(struct brcmnand_soc *soc, bool prepare)
static int iproc_nand_probe(struct platform_device *pdev)
{
+ u32 reset;
struct device *dev = &pdev->dev;
struct iproc_nand_soc_priv *priv;
struct brcmnand_soc *soc;
@@ -124,6 +130,19 @@ static int iproc_nand_probe(struct platform_device *pdev)
soc->ctlrdy_set_enabled = iproc_nand_intc_set;
soc->prepare_data_bus = iproc_nand_apb_access;
+ if (of_property_read_bool(dev->of_node, "brcm,nand-iproc-reset")) {
+ /* Put controller in reset and wait 10 usecs */
+ reset = readl(priv->idm_base + IPROC_NAND_RESET_OFFSET);
+ reset |= IPROC_NAND_RESET_BIT;
+ writel(reset, priv->idm_base + IPROC_NAND_RESET_OFFSET);
+ udelay(10);
+ /* Bring controller out of reset and wait 10 usecs */
+ reset = readl(priv->idm_base + IPROC_NAND_RESET_OFFSET);
+ reset &= ~IPROC_NAND_RESET_BIT;
+ writel(reset, priv->idm_base + IPROC_NAND_RESET_OFFSET);
+ udelay(10);
+ }
+
return brcmnand_probe(pdev, soc);
}
--
1.9.1
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