diff options
Diffstat (limited to 'src/cpu/ti/am335x/uart.c')
| -rw-r--r-- | src/cpu/ti/am335x/uart.c | 185 |
1 files changed, 0 insertions, 185 deletions
diff --git a/src/cpu/ti/am335x/uart.c b/src/cpu/ti/am335x/uart.c deleted file mode 100644 index a8823400ad..0000000000 --- a/src/cpu/ti/am335x/uart.c +++ /dev/null @@ -1,185 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0-or-later */ - -#include <types.h> -#include <console/uart.h> -#include <device/mmio.h> -#include <boot/coreboot_tables.h> -#include <cpu/ti/am335x/uart.h> - -#define EFR_ENHANCED_EN (1 << 4) -#define FCR_FIFO_EN (1 << 0) -#define MCR_TCR_TLR (1 << 6) -#define SYSC_SOFTRESET (1 << 1) -#define SYSS_RESETDONE (1 << 0) - -#define LSR_RXFIFOE (1 << 0) -#define LSR_TXFIFOE (1 << 5) - -/* - * Initialise the serial port with the given baudrate divisor. The settings - * are always 8 data bits, no parity, 1 stop bit, no start bits. - */ -static void am335x_uart_init(struct am335x_uart *uart, uint16_t div) -{ - uint16_t lcr_orig, efr_orig, mcr_orig; - - /* reset the UART */ - write16(&uart->sysc, uart->sysc | SYSC_SOFTRESET); - while (!(read16(&uart->syss) & SYSS_RESETDONE)) - ; - - /* 1. switch to register config mode B */ - lcr_orig = read16(&uart->lcr); - write16(&uart->lcr, 0xbf); - - /* - * 2. Set EFR ENHANCED_EN bit. To access this bit, registers must - * be in TCR_TLR submode, meaning EFR[4] = 1 and MCR[6] = 1. - */ - efr_orig = read16(&uart->efr); - write16(&uart->efr, efr_orig | EFR_ENHANCED_EN); - - /* 3. Switch to register config mode A */ - write16(&uart->lcr, 0x80); - - /* 4. Enable register submode TCR_TLR to access the UARTi.UART_TLR */ - mcr_orig = read16(&uart->mcr); - write16(&uart->mcr, mcr_orig | MCR_TCR_TLR); - - /* 5. Enable the FIFO. For now we'll ignore FIFO triggers and DMA */ - write16(&uart->fcr, FCR_FIFO_EN); - - /* 6. Switch to configuration mode B */ - write16(&uart->lcr, 0xbf); - /* Skip steps 7 and 8 (setting up FIFO triggers for DMA) */ - - /* 9. Restore original EFR value */ - write16(&uart->efr, efr_orig); - - /* 10. Switch to config mode A */ - write16(&uart->lcr, 0x80); - - /* 11. Restore original MCR value */ - write16(&uart->mcr, mcr_orig); - - /* 12. Restore original LCR value */ - write16(&uart->lcr, lcr_orig); - - /* Protocol, baud rate and interrupt settings */ - - /* 1. Disable UART access to DLL and DLH registers */ - write16(&uart->mdr1, read16(&uart->mdr1) | 0x7); - - /* 2. Switch to config mode B */ - write16(&uart->lcr, 0xbf); - - /* 3. Enable access to IER[7:4] */ - write16(&uart->efr, efr_orig | EFR_ENHANCED_EN); - - /* 4. Switch to operational mode */ - write16(&uart->lcr, 0x0); - - /* 5. Clear IER */ - write16(&uart->ier, 0x0); - - /* 6. Switch to config mode B */ - write16(&uart->lcr, 0xbf); - - /* 7. Set dll and dlh to the desired values (table 19-25) */ - write16(&uart->dlh, (div >> 8)); - write16(&uart->dll, (div & 0xff)); - - /* 8. Switch to operational mode to access ier */ - write16(&uart->lcr, 0x0); - - /* 9. Clear ier to disable all interrupts */ - write16(&uart->ier, 0x0); - - /* 10. Switch to config mode B */ - write16(&uart->lcr, 0xbf); - - /* 11. Restore efr */ - write16(&uart->efr, efr_orig); - - /* 12. Set protocol formatting 8n1 (8 bit data, no parity, 1 stop bit) */ - write16(&uart->lcr, 0x3); - - /* 13. Load the new UART mode */ - write16(&uart->mdr1, 0x0); -} - -/* - * Read a single byte from the serial port. Returns 1 on success, 0 - * otherwise. When the function is successful, the character read is - * written into its argument c. - */ -static unsigned char am335x_uart_rx_byte(struct am335x_uart *uart) -{ - while (!(read16(&uart->lsr) & LSR_RXFIFOE)); - - return read8(&uart->rhr); -} - -/* - * Output a single byte to the serial port. - */ -static void am335x_uart_tx_byte(struct am335x_uart *uart, unsigned char data) -{ - while (!(read16(&uart->lsr) & LSR_TXFIFOE)); - - return write8(&uart->thr, data); -} - -unsigned int uart_platform_refclk(void) -{ - return 48000000; -} - -uintptr_t uart_platform_base(int idx) -{ - const unsigned int bases[] = { - 0x44e09000, 0x48022000, 0x48024000, - 0x481a6000, 0x481a8000, 0x481aa000 - }; - if (idx < ARRAY_SIZE(bases)) - return bases[idx]; - return 0; -} - -void uart_init(int idx) -{ - struct am335x_uart *uart = uart_platform_baseptr(idx); - uint16_t div = (uint16_t) uart_baudrate_divisor( - get_uart_baudrate(), uart_platform_refclk(), 16); - am335x_uart_init(uart, div); -} - -unsigned char uart_rx_byte(int idx) -{ - struct am335x_uart *uart = uart_platform_baseptr(idx); - return am335x_uart_rx_byte(uart); -} - -void uart_tx_byte(int idx, unsigned char data) -{ - struct am335x_uart *uart = uart_platform_baseptr(idx); - am335x_uart_tx_byte(uart, data); -} - -void uart_tx_flush(int idx) -{ -} - -void uart_fill_lb(void *data) -{ - struct lb_serial serial; - serial.type = LB_SERIAL_TYPE_MEMORY_MAPPED; - serial.baseaddr = uart_platform_base(CONFIG_UART_FOR_CONSOLE); - serial.baud = get_uart_baudrate(); - serial.regwidth = 2; - serial.input_hertz = uart_platform_refclk(); - serial.uart_pci_addr = CONFIG_UART_PCI_ADDR; - lb_add_serial(&serial, data); - - lb_add_console(LB_TAG_CONSOLE_SERIAL8250MEM, data); -} |