[U-Boot-Users] i.MX31: mx31_gpio_mux() problem

[Magnus Lilja]

Hi all


While I was using the mx31_gpio_mux() function in cpu/arm1136/mx31/generic.c to modify the IOMUX for some IO pads I discovered that only the first 256 pads can be modified by this function.

It's pretty easy to fix this (see patch below) but I wonder if it's really the right way to fix this problem. Currently mx31_gpio_mux() takes only one argument, mode, which contains both the pad number and the new mode.

Current use:
mx31_gpio_mux((MUX_CTL_FUNC << 8) | MUX_CTL_CSPI2_MISO);

(the patch below changes << 8 to << 9 and modifies the mx31_gpiomux() function accordingly)

Perhaps it's better to split the above into two arguments, pad number and pad mode, the function will then be called with:
mx31_gpio_mux(MUX_CTL_CSPI2_MISO, MUX_CTL_FUNC);

I prefer the second approach (i.e. not the one in the patch below).

Any comments on which solution we prefer?

Regards, Magnus Lilja

---

 board/imx31_litekit/imx31_litekit.c   |   14 +++++++-------
 board/mx31ads/mx31ads.c               |   14 +++++++-------
 cpu/arm1136/mx31/generic.c            |    4 ++--
 include/asm-arm/arch-mx31/mx31-regs.h |   12 ++++++------
 4 files changed, 22 insertions(+), 22 deletions(-)

diff --git a/board/imx31_litekit/imx31_litekit.c b/board/imx31_litekit/imx31_litekit.c
index 263dd9f..09ce6f8 100644
--- a/board/imx31_litekit/imx31_litekit.c
+++ b/board/imx31_litekit/imx31_litekit.c
@@ -53,13 +53,13 @@ int board_init (void)
 	mx31_gpio_mux(MUX_RTS1__UART1_CTS_B);
 
 	/* SPI2 */
-	mx31_gpio_mux((MUX_CTL_FUNC << 8) | MUX_CTL_CSPI2_SS2);
-	mx31_gpio_mux((MUX_CTL_FUNC << 8) | MUX_CTL_CSPI2_SCLK);
-	mx31_gpio_mux((MUX_CTL_FUNC << 8) | MUX_CTL_CSPI2_SPI_RDY);
-	mx31_gpio_mux((MUX_CTL_FUNC << 8) | MUX_CTL_CSPI2_MOSI);
-	mx31_gpio_mux((MUX_CTL_FUNC << 8) | MUX_CTL_CSPI2_MISO);
-	mx31_gpio_mux((MUX_CTL_FUNC << 8) | MUX_CTL_CSPI2_SS0);
-	mx31_gpio_mux((MUX_CTL_FUNC << 8) | MUX_CTL_CSPI2_SS1);
+	mx31_gpio_mux((MUX_CTL_FUNC << 9) | MUX_CTL_CSPI2_SS2);
+	mx31_gpio_mux((MUX_CTL_FUNC << 9) | MUX_CTL_CSPI2_SCLK);
+	mx31_gpio_mux((MUX_CTL_FUNC << 9) | MUX_CTL_CSPI2_SPI_RDY);
+	mx31_gpio_mux((MUX_CTL_FUNC << 9) | MUX_CTL_CSPI2_MOSI);
+	mx31_gpio_mux((MUX_CTL_FUNC << 9) | MUX_CTL_CSPI2_MISO);
+	mx31_gpio_mux((MUX_CTL_FUNC << 9) | MUX_CTL_CSPI2_SS0);
+	mx31_gpio_mux((MUX_CTL_FUNC << 9) | MUX_CTL_CSPI2_SS1);
 
 	/* start SPI2 clock */
 	__REG(CCM_CGR2) = __REG(CCM_CGR2) | (3 << 4);
diff --git a/board/mx31ads/mx31ads.c b/board/mx31ads/mx31ads.c
index dd0e150..b29d1b0 100644
--- a/board/mx31ads/mx31ads.c
+++ b/board/mx31ads/mx31ads.c
@@ -58,13 +58,13 @@ int board_init (void)
 	mx31_gpio_mux(MUX_RTS1__UART1_CTS_B);
 
 	/* SPI2 */
-	mx31_gpio_mux((MUX_CTL_FUNC << 8) | MUX_CTL_CSPI2_SS2);
-	mx31_gpio_mux((MUX_CTL_FUNC << 8) | MUX_CTL_CSPI2_SCLK);
-	mx31_gpio_mux((MUX_CTL_FUNC << 8) | MUX_CTL_CSPI2_SPI_RDY);
-	mx31_gpio_mux((MUX_CTL_FUNC << 8) | MUX_CTL_CSPI2_MOSI);
-	mx31_gpio_mux((MUX_CTL_FUNC << 8) | MUX_CTL_CSPI2_MISO);
-	mx31_gpio_mux((MUX_CTL_FUNC << 8) | MUX_CTL_CSPI2_SS0);
-	mx31_gpio_mux((MUX_CTL_FUNC << 8) | MUX_CTL_CSPI2_SS1);
+	mx31_gpio_mux((MUX_CTL_FUNC << 9) | MUX_CTL_CSPI2_SS2);
+	mx31_gpio_mux((MUX_CTL_FUNC << 9) | MUX_CTL_CSPI2_SCLK);
+	mx31_gpio_mux((MUX_CTL_FUNC << 9) | MUX_CTL_CSPI2_SPI_RDY);
+	mx31_gpio_mux((MUX_CTL_FUNC << 9) | MUX_CTL_CSPI2_MOSI);
+	mx31_gpio_mux((MUX_CTL_FUNC << 9) | MUX_CTL_CSPI2_MISO);
+	mx31_gpio_mux((MUX_CTL_FUNC << 9) | MUX_CTL_CSPI2_SS0);
+	mx31_gpio_mux((MUX_CTL_FUNC << 9) | MUX_CTL_CSPI2_SS1);
 
 	/* start SPI2 clock */
 	__REG(CCM_CGR2) = __REG(CCM_CGR2) | (3 << 4);
diff --git a/cpu/arm1136/mx31/generic.c b/cpu/arm1136/mx31/generic.c
index 29c08c1..f897a2a 100644
--- a/cpu/arm1136/mx31/generic.c
+++ b/cpu/arm1136/mx31/generic.c
@@ -81,12 +81,12 @@ void mx31_gpio_mux(unsigned long mode)
 {
 	unsigned long reg, shift, tmp;
 
-	reg = IOMUXC_BASE + (mode & 0xfc);
+	reg = IOMUXC_BASE + (mode & 0x1fc);
 	shift = (~mode & 0x3) * 8;
 
 	tmp = __REG(reg);
 	tmp &= ~(0xff << shift);
-	tmp |= ((mode >> 8) & 0xff) << shift;
+	tmp |= ((mode >> 9) & 0xff) << shift;
 	__REG(reg) = tmp;
 }
 
diff --git a/include/asm-arm/arch-mx31/mx31-regs.h b/include/asm-arm/arch-mx31/mx31-regs.h
index 02b7dcb..b1c6327 100644
--- a/include/asm-arm/arch-mx31/mx31-regs.h
+++ b/include/asm-arm/arch-mx31/mx31-regs.h
@@ -130,13 +130,13 @@
  * these macros can be used in mx31_gpio_mux() and have the form
  * MUX_[contact name]__[pin function]
  */
-#define MUX_RXD1__UART1_RXD_MUX	((MUX_CTL_FUNC << 8) | MUX_CTL_RXD1)
-#define MUX_TXD1__UART1_TXD_MUX	((MUX_CTL_FUNC << 8) | MUX_CTL_TXD1)
-#define MUX_RTS1__UART1_RTS_B	((MUX_CTL_FUNC << 8) | MUX_CTL_RTS1)
-#define MUX_RTS1__UART1_CTS_B	((MUX_CTL_FUNC << 8) | MUX_CTL_CTS1)
+#define MUX_RXD1__UART1_RXD_MUX	((MUX_CTL_FUNC << 9) | MUX_CTL_RXD1)
+#define MUX_TXD1__UART1_TXD_MUX	((MUX_CTL_FUNC << 9) | MUX_CTL_TXD1)
+#define MUX_RTS1__UART1_RTS_B	((MUX_CTL_FUNC << 9) | MUX_CTL_RTS1)
+#define MUX_RTS1__UART1_CTS_B	((MUX_CTL_FUNC << 9) | MUX_CTL_CTS1)
 
-#define MUX_CSPI2_MOSI__I2C2_SCL ((MUX_CTL_ALT1 << 8) | MUX_CTL_CSPI2_MOSI)
-#define MUX_CSPI2_MISO__I2C2_SCL ((MUX_CTL_ALT1 << 8) | MUX_CTL_CSPI2_MISO)
+#define MUX_CSPI2_MOSI__I2C2_SCL ((MUX_CTL_ALT1 << 9) | MUX_CTL_CSPI2_MOSI)
+#define MUX_CSPI2_MISO__I2C2_SCL ((MUX_CTL_ALT1 << 9) | MUX_CTL_CSPI2_MISO)
 
 /*
  * Memory regions and CS