lkml.org 
[lkml]   [2017]   [Apr]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v1 1/1] mtd: mtk-nor: set controller's address width according to nor flash
Date
When nor's size larger than 16MByte, nor's address width maybe
set to 3 or 4, and controller should change address width according
to nor's setting.

Signed-off-by: Guochun Mao <guochun.mao@mediatek.com>
---
drivers/mtd/spi-nor/mtk-quadspi.c | 27 +++++++++++++++++++++++++++
1 file changed, 27 insertions(+)

diff --git a/drivers/mtd/spi-nor/mtk-quadspi.c b/drivers/mtd/spi-nor/mtk-quadspi.c
index e661877..b637770 100644
--- a/drivers/mtd/spi-nor/mtk-quadspi.c
+++ b/drivers/mtd/spi-nor/mtk-quadspi.c
@@ -104,6 +104,8 @@
#define MTK_NOR_MAX_RX_TX_SHIFT 6
/* can shift up to 56 bits (7 bytes) transfer by MTK_NOR_PRG_CMD */
#define MTK_NOR_MAX_SHIFT 7
+/* nor controller 4-byte address mode enable bit */
+#define MTK_NOR_4B_ADDR_EN BIT(4)

/* Helpers for accessing the program data / shift data registers */
#define MTK_NOR_PRG_REG(n) (MTK_NOR_PRGDATA0_REG + 4 * (n))
@@ -230,10 +232,35 @@ static int mt8173_nor_write_buffer_disable(struct mt8173_nor *mt8173_nor)
10000);
}

+static void mt8173_nor_set_addr_width(struct mt8173_nor *mt8173_nor)
+{
+ u8 val;
+ struct spi_nor *nor = &mt8173_nor->nor;
+
+ val = readb(mt8173_nor->base + MTK_NOR_DUAL_REG);
+
+ switch (nor->addr_width) {
+ case 3:
+ val &= ~MTK_NOR_4B_ADDR_EN;
+ break;
+ case 4:
+ val |= MTK_NOR_4B_ADDR_EN;
+ break;
+ default:
+ dev_warn(mt8173_nor->dev, "Unexpected address width %u.\n",
+ nor->addr_width);
+ break;
+ }
+
+ writeb(val, mt8173_nor->base + MTK_NOR_DUAL_REG);
+}
+
static void mt8173_nor_set_addr(struct mt8173_nor *mt8173_nor, u32 addr)
{
int i;

+ mt8173_nor_set_addr_width(mt8173_nor);
+
for (i = 0; i < 3; i++) {
writeb(addr & 0xff, mt8173_nor->base + MTK_NOR_RADR0_REG + i * 4);
addr >>= 8;
--
1.7.9.5
\
 
 \ /
  Last update: 2017-04-05 10:43    [W:0.062 / U:1.892 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site