diff options
Diffstat (limited to 'roms/u-boot/drivers/serial/arm_dcc.c')
| -rw-r--r-- | roms/u-boot/drivers/serial/arm_dcc.c | 174 |
1 files changed, 174 insertions, 0 deletions
diff --git a/roms/u-boot/drivers/serial/arm_dcc.c b/roms/u-boot/drivers/serial/arm_dcc.c new file mode 100644 index 000000000..dfcb6fd69 --- /dev/null +++ b/roms/u-boot/drivers/serial/arm_dcc.c @@ -0,0 +1,174 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2004-2007 ARM Limited. + * Copyright (C) 2008 Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> + * Copyright (C) 2015 - 2016 Xilinx, Inc, Michal Simek + * + * As a special exception, if other files instantiate templates or use macros + * or inline functions from this file, or you compile this file and link it + * with other works to produce a work based on this file, this file does not + * by itself cause the resulting work to be covered by the GNU General Public + * License. However the source code for this file must still be made available + * in accordance with section (3) of the GNU General Public License. + + * This exception does not invalidate any other reasons why a work based on + * this file might be covered by the GNU General Public License. + */ + +#include <common.h> +#include <dm.h> +#include <serial.h> + +#if defined(CONFIG_CPU_V6) || defined(CONFIG_CPU_V7A) || defined(CONFIG_CPU_V7R) +/* + * ARMV6 & ARMV7 + */ +#define DCC_RBIT (1 << 30) +#define DCC_WBIT (1 << 29) + +#define write_dcc(x) \ + __asm__ volatile ("mcr p14, 0, %0, c0, c5, 0\n" : : "r" (x)) + +#define read_dcc(x) \ + __asm__ volatile ("mrc p14, 0, %0, c0, c5, 0\n" : "=r" (x)) + +#define status_dcc(x) \ + __asm__ volatile ("mrc p14, 0, %0, c0, c1, 0\n" : "=r" (x)) + +#elif defined(CONFIG_CPU_XSCALE) +/* + * XSCALE + */ +#define DCC_RBIT (1 << 31) +#define DCC_WBIT (1 << 28) + +#define write_dcc(x) \ + __asm__ volatile ("mcr p14, 0, %0, c8, c0, 0\n" : : "r" (x)) + +#define read_dcc(x) \ + __asm__ volatile ("mrc p14, 0, %0, c9, c0, 0\n" : "=r" (x)) + +#define status_dcc(x) \ + __asm__ volatile ("mrc p14, 0, %0, c14, c0, 0\n" : "=r" (x)) + +#elif defined(CONFIG_CPU_ARMV8) +/* + * ARMV8 + */ +#define DCC_RBIT (1 << 30) +#define DCC_WBIT (1 << 29) + +#define write_dcc(x) \ + __asm__ volatile ("msr dbgdtrtx_el0, %0\n" : : "r" (x)) + +#define read_dcc(x) \ + __asm__ volatile ("mrs %0, dbgdtrrx_el0\n" : "=r" (x)) + +#define status_dcc(x) \ + __asm__ volatile ("mrs %0, mdccsr_el0\n" : "=r" (x)) + +#else +#define DCC_RBIT (1 << 0) +#define DCC_WBIT (1 << 1) + +#define write_dcc(x) \ + __asm__ volatile ("mcr p14, 0, %0, c1, c0, 0\n" : : "r" (x)) + +#define read_dcc(x) \ + __asm__ volatile ("mrc p14, 0, %0, c1, c0, 0\n" : "=r" (x)) + +#define status_dcc(x) \ + __asm__ volatile ("mrc p14, 0, %0, c0, c0, 0\n" : "=r" (x)) + +#endif + +#define can_read_dcc(x) do { \ + status_dcc(x); \ + x &= DCC_RBIT; \ + } while (0); + +#define can_write_dcc(x) do { \ + status_dcc(x); \ + x &= DCC_WBIT; \ + x = (x == 0); \ + } while (0); + +#define TIMEOUT_COUNT 0x4000000 + +static int arm_dcc_getc(struct udevice *dev) +{ + int ch; + register unsigned int reg; + + do { + can_read_dcc(reg); + } while (!reg); + read_dcc(ch); + + return ch; +} + +static int arm_dcc_putc(struct udevice *dev, char ch) +{ + register unsigned int reg; + unsigned int timeout_count = TIMEOUT_COUNT; + + while (--timeout_count) { + can_write_dcc(reg); + if (reg) + break; + } + if (timeout_count == 0) + return -EAGAIN; + else + write_dcc(ch); + + return 0; +} + +static int arm_dcc_pending(struct udevice *dev, bool input) +{ + register unsigned int reg; + + if (input) { + can_read_dcc(reg); + } else { + can_write_dcc(reg); + } + + return reg; +} + +static const struct dm_serial_ops arm_dcc_ops = { + .putc = arm_dcc_putc, + .pending = arm_dcc_pending, + .getc = arm_dcc_getc, +}; + +static const struct udevice_id arm_dcc_ids[] = { + { .compatible = "arm,dcc", }, + { } +}; + +U_BOOT_DRIVER(serial_dcc) = { + .name = "arm_dcc", + .id = UCLASS_SERIAL, + .of_match = arm_dcc_ids, + .ops = &arm_dcc_ops, +}; + +#ifdef CONFIG_DEBUG_UART_ARM_DCC + +#include <debug_uart.h> + +static inline void _debug_uart_init(void) +{ +} + +static inline void _debug_uart_putc(int ch) +{ + arm_dcc_putc(NULL, ch); +} + +DEBUG_UART_FUNCS +#endif |