[U-Boot-Users] [PATCH (RESUBMIT)] ppc4xx: Add functionality to GPIO support
Lawrence R. Johnson
lrj at acm.org
Fri Jan 4 00:54:00 CET 2008
This patch makes two additions to GPIO support:
First, it adds function gpio_read_in_bit() to read the a bit from the
GPIO Input Register (GPIOx_IR) in the same way that function
gpio_read_out_bit() reads a bit from the GPIO Output Register
(GPIOx_OR).
Second, it modifies function gpio_set_chip_configuration() to provide
an additional option for configuring the GPIO from the
"CFG_4xx_GPIO_TABLE".
According to the 440EPx User's Manual, when an alternate output is used,
the three-state control is configured in one of two ways, depending on
the particular output. The first option is to select the corresponding
alternate three-state control in the GPIOx_TRSH/L registers. The second
option is to select the GPIO Three-State Control Register (GPIOx_TCR) in
the GPIOx_TRSH/L registers, and set the corresponding bit in the
GPIOx_TCR register to enable the output. For example, the Manual
specifies configuring the GPIO00 Alternate 1 Signal (PreAddr07) to use
the alternate three-state control (first option), and specifies
configuring the GPIO32 Alternate 1 Signal (USB2OM0) with the output
enabled in the GPIOx_TCR register (second option).
Currently, gpio_set_chip_configuration() configures all alternate signal
outputs to use the first option. This patch allow the second option to
be selected by setting the "out_val" element in the table entry to
"GPIO_OUT_1". The first option is used when the "out_val" element is
set to "GPIO_OUT_0". Because "out_val" is not currently used when an
alternate signal is selected, and because all current GPIO tables set
"out_val" to "GPIO_OUT_0" for all alternate signals, this patch should
not change any existing configurations.
Signed-off-by: Larry Johnson <lrj at acm.org>
---
cpu/ppc4xx/gpio.c | 63 ++++++++++++++++++++++++++++++-----------------
include/asm-ppc/gpio.h | 1 +
2 files changed, 41 insertions(+), 23 deletions(-)
diff --git a/cpu/ppc4xx/gpio.c b/cpu/ppc4xx/gpio.c
index 7b09a2f..37d3fa8 100644
--- a/cpu/ppc4xx/gpio.c
+++ b/cpu/ppc4xx/gpio.c
@@ -27,7 +27,7 @@
#include <asm/gpio.h>
#if defined(CFG_4xx_GPIO_TABLE)
-gpio_param_s gpio_tab[GPIO_GROUP_MAX][GPIO_MAX] = CFG_4xx_GPIO_TABLE;
+gpio_param_s const gpio_tab[GPIO_GROUP_MAX][GPIO_MAX] = CFG_4xx_GPIO_TABLE;
#endif
#if defined(GPIO0_OSRL)
@@ -120,6 +120,18 @@ int gpio_read_out_bit(int pin)
return (in_be32((void *)GPIO0_OR + offs) & GPIO_VAL(pin) ? 1 : 0);
}
+int gpio_read_in_bit(int pin)
+{
+ u32 offs = 0;
+
+ if (pin >= GPIO_MAX) {
+ offs = 0x100;
+ pin -= GPIO_MAX;
+ }
+
+ return (in_be32((void *)GPIO0_IR + offs) & GPIO_VAL(pin) ? 1 : 0);
+}
+
#if defined(CFG_4xx_GPIO_TABLE)
void gpio_set_chip_configuration(void)
{
@@ -171,6 +183,8 @@ void gpio_set_chip_configuration(void)
if ((gpio_tab[gpio_core][i].in_out == GPIO_OUT) ||
(gpio_tab[gpio_core][i].in_out == GPIO_BI)) {
+ u32 gpio_alt_sel = 0;
+
switch (gpio_tab[gpio_core][i].alt_nb) {
case GPIO_SEL:
/*
@@ -199,37 +213,40 @@ void gpio_set_chip_configuration(void)
break;
case GPIO_ALT1:
- reg = in_be32((void *)GPIO_OS(core_add+offs))
- & ~(GPIO_MASK >> (j*2));
- reg = reg | (GPIO_ALT1_SEL >> (j*2));
- out_be32((void *)GPIO_OS(core_add+offs), reg);
- reg = in_be32((void *)GPIO_TS(core_add+offs))
- & ~(GPIO_MASK >> (j*2));
- reg = reg | (GPIO_ALT1_SEL >> (j*2));
- out_be32((void *)GPIO_TS(core_add+offs), reg);
+ gpio_alt_sel = GPIO_ALT1_SEL;
break;
case GPIO_ALT2:
- reg = in_be32((void *)GPIO_OS(core_add+offs))
- & ~(GPIO_MASK >> (j*2));
- reg = reg | (GPIO_ALT2_SEL >> (j*2));
- out_be32((void *)GPIO_OS(core_add+offs), reg);
- reg = in_be32((void *)GPIO_TS(core_add+offs))
- & ~(GPIO_MASK >> (j*2));
- reg = reg | (GPIO_ALT2_SEL >> (j*2));
- out_be32((void *)GPIO_TS(core_add+offs), reg);
+ gpio_alt_sel = GPIO_ALT2_SEL;
break;
case GPIO_ALT3:
+ gpio_alt_sel = GPIO_ALT3_SEL;
+ break;
+ }
+
+ if (0 != gpio_alt_sel) {
reg = in_be32((void *)GPIO_OS(core_add+offs))
& ~(GPIO_MASK >> (j*2));
- reg = reg | (GPIO_ALT3_SEL >> (j*2));
+ reg = reg | (gpio_alt_sel >> (j*2));
out_be32((void *)GPIO_OS(core_add+offs), reg);
- reg = in_be32((void *)GPIO_TS(core_add+offs))
- & ~(GPIO_MASK >> (j*2));
- reg = reg | (GPIO_ALT3_SEL >> (j*2));
- out_be32((void *)GPIO_TS(core_add+offs), reg);
- break;
+
+ if (gpio_tab[gpio_core][i].out_val == GPIO_OUT_1) {
+ reg = in_be32((void *)GPIO_TCR(core_add))
+ | (0x80000000 >> (i));
+ out_be32((void *)GPIO_TCR(core_add), reg);
+ reg = in_be32((void *)GPIO_TS(core_add+offs))
+ & ~(GPIO_MASK >> (j*2));
+ out_be32((void *)GPIO_TS(core_add+offs), reg);
+ } else {
+ reg = in_be32((void *)GPIO_TCR(core_add))
+ & ~(0x80000000 >> (i));
+ out_be32((void *)GPIO_TCR(core_add), reg);
+ reg = in_be32((void *)GPIO_TS(core_add+offs))
+ & ~(GPIO_MASK >> (j*2));
+ reg = reg | (gpio_alt_sel >> (j*2));
+ out_be32((void *)GPIO_TS(core_add+offs), reg);
+ }
}
}
}
diff --git a/include/asm-ppc/gpio.h b/include/asm-ppc/gpio.h
index d0c3eba..c3a4a88 100644
--- a/include/asm-ppc/gpio.h
+++ b/include/asm-ppc/gpio.h
@@ -88,6 +88,7 @@ typedef struct {
void gpio_config(int pin, int in_out, int gpio_alt, int out_val);
void gpio_write_bit(int pin, int val);
int gpio_read_out_bit(int pin);
+int gpio_read_in_bit(int pin);
void gpio_set_chip_configuration(void);
#endif /* __ASM_PPC_GPIO_H */
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