From 8226dbbf1d85be662ab6d427ca80c305cf0b719d Mon Sep 17 00:00:00 2001 From: Alexandru Gagniuc Date: Sun, 22 Dec 2013 21:30:21 -0500 Subject: 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 Reviewed-on: http://review.coreboot.org/4565 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer --- src/cpu/allwinner/a10/gpio.h | 3 ++- src/cpu/allwinner/a10/pinmux.c | 51 +++++++++++++++++++++++++++++++++++++++++- 2 files changed, 52 insertions(+), 2 deletions(-) (limited to 'src/cpu/allwinner/a10') 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]); + } +} -- cgit v1.2.3