diff options
Diffstat (limited to 'platform/zynq/gpio.c')
| -rw-r--r-- | platform/zynq/gpio.c | 285 |
1 files changed, 0 insertions, 285 deletions
diff --git a/platform/zynq/gpio.c b/platform/zynq/gpio.c deleted file mode 100644 index a942f212..00000000 --- a/platform/zynq/gpio.c +++ /dev/null @@ -1,285 +0,0 @@ -/* - * Copyright (c) 2012-2015 Travis Geiselbrecht - * Copyright (c) 2015 Christopher Anderson - * - * Permission is hereby granted, free of charge, to any person obtaining - * a copy of this software and associated documentation files - * (the "Software"), to deal in the Software without restriction, - * including without limitation the rights to use, copy, modify, merge, - * publish, distribute, sublicense, and/or sell copies of the Software, - * and to permit persons to whom the Software is furnished to do so, - * subject to the following conditions: - * - * The above copyright notice and this permission notice shall be - * included in all copies or substantial portions of the Software. - * - * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, - * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF - * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. - * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY - * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, - * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE - * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. - */ -#include <assert.h> -#include <debug.h> -#include <reg.h> -#include <stdio.h> -#include <string.h> -#include <dev/gpio.h> -#include <platform/gpio.h> -#include <platform/interrupts.h> -#include <target/gpioconfig.h> - -#define MAX_GPIO 128 - -static inline uint16_t extract_bank(unsigned gpio_id) { return gpio_id / 32; } -static inline uint16_t extract_bit (unsigned gpio_id) { return gpio_id % 32; } - -struct { - int_handler callback; - void *args; -} irq_callbacks[MAX_GPIO]; - -static enum handler_return gpio_int_handler(void *arg) -{ - - /* The mask register uses 1 to respresent masked, 0 for unmasked. Comparing that - * register with the interrupt status register is the only way to determine - * which gpio triggered the interrupt in the gic. */ - for (uint32_t bank = 0; bank < 4; bank++) { - uint32_t mask = *REG32(GPIO_INT_MASK(bank)); - uint32_t stat = *REG32(GPIO_INT_STAT(bank)); - uint32_t active = ~mask & stat; - - if (active == 0) { - continue; - } - - //printf("mask 0x%08x stat 0x%08x active 0x%08x\n", mask, stat, active); - while (active) { - /* Find the rightmost set bit, calculate the associated gpio, and call the callback */ - uint16_t bit = 32 - clz(active) - 1; - uint16_t gpio = bit + (bank * 32); - - active ^= (1 << bit); - if (irq_callbacks[gpio].callback) { - irq_callbacks[gpio].callback(irq_callbacks[gpio].args); - } - //printf("bit %u bank %u gpio %u was triggered\n", bit, bank, gpio); - } - - *REG32(GPIO_INT_STAT(bank)) = stat; - } - - return 0; -} - -void zynq_unmask_gpio_interrupt(unsigned gpio) -{ - uint16_t bank = extract_bank(gpio); - uint16_t bit = extract_bit(gpio); - - RMWREG32(GPIO_INT_EN(bank), bit, 1, 1); - RMWREG32(GPIO_INT_STAT(bank), bit, 1, 1); -} - -void zynq_mask_gpio_interrupt(unsigned gpio) -{ - uint16_t bank = extract_bank(gpio); - uint16_t bit = extract_bit(gpio); - - RMWREG32(GPIO_INT_DIS(bank), bit, 1, 1); -} - - -void zynq_gpio_init(void) -{ - register_int_handler(GPIO_INT, gpio_int_handler, NULL); - unmask_interrupt(GPIO_INT); - - // Note(johngro): - // - // The Zynq 700 series documentation describes two bits which affect the - // input vs. output nature of the GPIOs (DIRM and OEN, or output enable). - // On the surface, the docs seem to indicate that they do the same thing, - // which is to enable or disable the output driver on the pin. The docs - // make it clear that the input function is always enabled, regardless of - // the settings of either the DIRM or OEN bits (input state is readable via - // the DATA_RO registers). Also, they state that the output drivers cannot - // be enabled if the TRISTATE bit is set on the pin in the SLCR unit. - // - // In practice, however, there seems to be a subtle, undocumented, - // difference between these bits (At least whent the GPIOs in question are - // MIOs, this behavior has not been verified on EMIOs). - // - // The OEN bit seems to do what you would want it to do (toggle the output - // drivers on and off). The desired drive state of the pin (reflected in - // the DATA and MASK_DATA registers) holds the user setting regardless of - // the state of the OEN bit, and the state of the line can be read via the - // DATA_RO bit. - // - // When the DIRM bit is cleared, however, the state of the line seems to - // become latched into the desired drive state of the pin instead of holding - // its last programmed state. For example; say the pin is being used to - // as a line in an open collector bus, such as i2c. The output drivers - // are enabled (OEN and DIRM == 1), and the pin is being driven low (DATA == - // 0). When it comes time to release the line, if a user clears OEN, the - // driver will be disabled and the line will be pulled high by the external - // pullup. DATA will still read 0 (the desired drive state of the pin) and - // DATA_RO will read 1 (the actual state of the line). If, on the other - // hand, the user clears the DIRM bit instead of the OEN bit, the driver - // will be disabled and the line will be pulled high again, but this time - // DATA will latch the value of the line itself (DATA == 1, DATA_RO == 1). - // - // Because of this behvior, we NEVER use the DIRM bit to control the driver - // state of the pin. During init, set all pins to input mode by first - // clearing the OEN bits, and then making sure that the DIRM bits are all - // set. - for (unsigned int bank = 0; bank < 4; bank++) { - *REG32(GPIO_OEN(bank)) = 0x00000000; - *REG32(GPIO_DIRM(bank)) = 0xFFFFFFFF; - } -} - -void zynq_gpio_early_init(void) -{ -} - -void register_gpio_int_handler(unsigned gpio, int_handler handler, void *args) -{ - DEBUG_ASSERT(gpio < MAX_GPIO); - DEBUG_ASSERT(handler); - - irq_callbacks[gpio].callback = handler; - irq_callbacks[gpio].args = args; -} - -void unregister_gpio_int_handler(unsigned gpio) -{ - DEBUG_ASSERT(gpio < MAX_GPIO); - - irq_callbacks[gpio].callback = NULL; - irq_callbacks[gpio].args = NULL; -} - -int gpio_config(unsigned gpio, unsigned flags) -{ - DEBUG_ASSERT(gpio < MAX_GPIO); - - uint16_t bank = extract_bank(gpio); - uint16_t bit = extract_bit(gpio); - - /* MIO region, exclude EMIO. MIO needs to be configured before the GPIO block. */ - if (bank < 2) { - // Preserve all of the fields of the current pin configuration, except - // for PULLUP and the MUX configurtaion. Force the mux config to select - // GPIO mode, and turn the pullup on or off as requested by the user. - uint32_t mio_cfg = SLCR_REG(MIO_PIN_00 + (gpio * 4)); - mio_cfg &= MIO_TRI_ENABLE | - MIO_SPEED_FAST | - MIO_IO_TYPE_MASK | - MIO_DISABLE_RCVR; - - // No need to set any bits in the L[0123]_SEL fields; we want them to - // all be zero. - - if (flags & GPIO_PULLUP) { - mio_cfg |= MIO_PULLUP; - } - - SLCR_REG(MIO_PIN_00 + (gpio * 4)) = mio_cfg; - } - - if (flags & GPIO_OUTPUT || flags & GPIO_INPUT) { - if (flags & GPIO_OUTPUT && flags & GPIO_INPUT) { - printf("Cannot configure a gpio as both an input and output direction.\n"); - return -1; - } - - // Note(johngro): use only the OEN bit to control the output driver. Do - // not use the DIRM bit; see the note in zynq_gpio_init. - RMWREG32(GPIO_OEN(bank), bit, 1, ((flags & GPIO_OUTPUT) > 0)); - } - - if (flags & GPIO_EDGE || flags & GPIO_LEVEL) { - if (flags & GPIO_EDGE && flags & GPIO_LEVEL) { - printf("Cannot configure a gpio as both edge and level sensitive.\n"); - return -1; - } - RMWREG32(GPIO_INT_TYPE(bank), bit, 1, ((flags & GPIO_EDGE) > 0)); - } - - if (flags & GPIO_RISING || flags & GPIO_FALLING) { - /* Zynq has a specific INT_ANY register for handling interrupts that trigger on both - * rising and falling edges, but it specifically must only be used in edge mode */ - if (flags & GPIO_RISING && flags & GPIO_FALLING) { - if ((flags & GPIO_EDGE) == 0) { - printf("polarity must be rising or falling if level sensitivity is used.\n"); - return -1; - } - - RMWREG32(GPIO_INT_ANY(bank), bit, 1, 1); - } else { - RMWREG32(GPIO_INT_POLARITY(bank), bit, 1, ((flags & GPIO_RISING) > 0)); - RMWREG32(GPIO_INT_ANY(bank), bit, 1, 0); - } - } - - return 0; -} - -void gpio_set(unsigned gpio, unsigned on) -{ - DEBUG_ASSERT(gpio < MAX_GPIO); - - uint16_t bank = extract_bank(gpio); - uint16_t bit = extract_bit(gpio); - uintptr_t reg; - - if (bit < 16) { - reg = GPIO_MASK_DATA_LSW(bank); - } else { - reg = GPIO_MASK_DATA_MSW(bank); - bit -= 16; - } - - *REG32(reg) = (~(1 << bit) << 16) | (!!on << bit); -} - -int gpio_get(unsigned gpio) -{ - DEBUG_ASSERT(gpio < MAX_GPIO); - - uint16_t bank = extract_bank(gpio); - uint16_t bit = extract_bit(gpio); - - return ((*REG32(GPIO_DATA_RO(bank)) & (1 << bit)) > 0); -} - -#include <lib/console.h> -#ifdef WITH_LIB_CONSOLE -static int cmd_zynq_gpio(int argc, const cmd_args *argv) -{ - for (unsigned int bank = 0; bank < 4; bank++) { - printf("DIRM_%u (0x%08x): 0x%08x\n", bank, GPIO_DIRM(bank), *REG32(GPIO_DIRM(bank))); - printf("OEN_%u (0x%08x): 0x%08x\n", bank, GPIO_OEN(bank), *REG32(GPIO_OEN(bank))); - printf("MASK_DATA_LSW_%u (0x%08x): 0x%08x\n", bank, GPIO_MASK_DATA_LSW(bank), *REG32(GPIO_MASK_DATA_LSW(bank))); - printf("MASK_DATA_MSW_%u (0x%08x): 0x%08x\n", bank, GPIO_MASK_DATA_MSW(bank), *REG32(GPIO_MASK_DATA_MSW(bank))); - printf("DATA_%u (0x%08x): 0x%08x\n", bank, GPIO_DATA(bank), *REG32(GPIO_DATA(bank))); - printf("DATA_RO_%u (0x%08x): 0x%08x\n", bank, GPIO_DATA_RO(bank), *REG32(GPIO_DATA_RO(bank))); - printf("INT_MASK_%u (0x%08x): 0x%08x\n", bank, GPIO_INT_MASK(bank), *REG32(GPIO_INT_MASK(bank))); - printf("INT_STAT_%u (0x%08x): 0x%08x\n", bank, GPIO_INT_STAT(bank), *REG32(GPIO_INT_STAT(bank))); - printf("INT_TYPE_%u (0x%08x): 0x%08x\n", bank, GPIO_INT_TYPE(bank), *REG32(GPIO_INT_TYPE(bank))); - printf("INT_POLARITY_%u (0x%08x): 0x%08x\n", bank, GPIO_INT_POLARITY(bank), *REG32(GPIO_INT_POLARITY(bank))); - printf("INT_ANY_%u (0x%08x): 0x%08x\n", bank, GPIO_INT_ANY(bank), *REG32(GPIO_INT_ANY(bank))); - } - return 0; -} -STATIC_COMMAND_START -#if LK_DEBUGLEVEL > 1 -STATIC_COMMAND("zynq_gpio", "Dump Zynq GPIO registers", &cmd_zynq_gpio) -#endif -STATIC_COMMAND_END(zynq_gpio); - -#endif |