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authorAlexandru Gagniuc <mr.nuke.me@gmail.com>2013-12-22 21:30:21 -0500
committerAlexandru Gagniuc <mr.nuke.me@gmail.com>2014-01-08 23:03:19 +0100
commit8226dbbf1d85be662ab6d427ca80c305cf0b719d (patch)
tree3f284c9b105396fc757245da6db5bee30fd3688e /src/cpu/allwinner
parentbe32f51aa180bd132caa790452b8c0e7920c3afb (diff)
downloadcoreboot-8226dbbf1d85be662ab6d427ca80c305cf0b719d.tar.xz
cpu/allwinner/a10: Refactor and document pinmux API
Include a function to multiplex more than one pin at a time. This is useful for peripherals that have the same function number for all their pins. Since we now have two functions for muxing pins, also document them. Change-Id: I53997cc3a2586e3cf749cd672f69fb427659c67f Signed-off-by: Alexandru Gagniuc <mr.nuke.me@gmail.com> Reviewed-on: http://review.coreboot.org/4565 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Diffstat (limited to 'src/cpu/allwinner')
-rw-r--r--src/cpu/allwinner/a10/gpio.h3
-rw-r--r--src/cpu/allwinner/a10/pinmux.c51
2 files changed, 52 insertions, 2 deletions
diff --git a/src/cpu/allwinner/a10/gpio.h b/src/cpu/allwinner/a10/gpio.h
index f285451b17..709f74b641 100644
--- a/src/cpu/allwinner/a10/gpio.h
+++ b/src/cpu/allwinner/a10/gpio.h
@@ -46,6 +46,7 @@ struct a10_gpio {
u32 sdr_pad_pul;
} __attribute__ ((packed));
-void gpio_set_func(u8 port, u8 pin, u8 pad_func);
+void gpio_set_pin_func(u8 port, u8 pin, u8 pad_func);
+void gpio_set_multipin_func(u8 port, u32 pin_mask, u8 pad_func);
#endif /* __CPU_ALLWINNER_A10_PINMUX_H */
diff --git a/src/cpu/allwinner/a10/pinmux.c b/src/cpu/allwinner/a10/pinmux.c
index 2525de58af..de87440d8f 100644
--- a/src/cpu/allwinner/a10/pinmux.c
+++ b/src/cpu/allwinner/a10/pinmux.c
@@ -11,7 +11,14 @@
static struct a10_gpio *const gpio = (void *)GPIO_BASE;
-void gpio_set_func(u8 port, u8 pin, u8 pad_func)
+/**
+ * \brief Set the pad function of a single pin
+ *
+ * @param[in] port GPIO port of the pin (GPA -> GPS)
+ * @param[in] pin the pin number in the given port (1 -> 31)
+ * @param[in] pad_func The peripheral function to which to connect this pin
+ */
+void gpio_set_pin_func(u8 port, u8 pin, u8 pad_func)
{
u8 reg, bit;
u32 reg32;
@@ -28,3 +35,45 @@ void gpio_set_func(u8 port, u8 pin, u8 pad_func)
reg32 |= (pad_func & 0xf) << bit;
write32(reg32, &gpio->port[port].cfg[reg]);
}
+
+/**
+ * \brief Set the pad function of a group of pins
+ *
+ * Multiplex a group of pins to the same pad function. This is useful for
+ * peripherals that use the same function number for several pins. This function
+ * allows those pins to be set with a single call.
+ *
+ * Example:
+ * gpio_set_multipin_func(GPB, (1 << 23) | (1 << 22), 2);
+ *
+ * @param[in] port GPIO port of the pin (GPA -> GPS)
+ * @param[in] pin_mask 32-bit mask indicating which pins to re-multiplex. For
+ * each set bit, the corresponding pin will be multiplexed.
+ * @param[in] pad_func The peripheral function to which to connect the pins
+ */
+void gpio_set_multipin_func(u8 port, u32 pin_mask, u8 pad_func)
+{
+ int j;
+ u8 reg, bit;
+ u32 reg32, mask_offset;
+
+ if ((port > GPS))
+ return;
+
+ for (reg = 0; reg < 4; reg++) {
+ mask_offset = 8 * reg;
+ /* Don't run the inner loop if we're not touching any pins */
+ if (!(pin_mask & (0xff << mask_offset)))
+ continue;
+
+ reg32 = read32(&gpio->port[port].cfg[reg]);
+ for (j = 0; j < 8; j++) {
+ if (!(pin_mask & (1 << (j + mask_offset))))
+ continue;
+ bit = j * 4;
+ reg32 &= ~(0xf << bit);
+ reg32 |= (pad_func & 0xf) << bit;
+ }
+ write32(reg32, &gpio->port[port].cfg[reg]);
+ }
+}