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Diffstat (limited to 'post/cpu/ppc4xx/uart.c')
| -rw-r--r-- | post/cpu/ppc4xx/uart.c | 214 |
1 files changed, 214 insertions, 0 deletions
diff --git a/post/cpu/ppc4xx/uart.c b/post/cpu/ppc4xx/uart.c new file mode 100644 index 0000000..f220dba --- /dev/null +++ b/post/cpu/ppc4xx/uart.c @@ -0,0 +1,214 @@ +/* + * (C) Copyright 2007 + * Wolfgang Denk, DENX Software Engineering, wd@denx.de. + * + * See file CREDITS for list of people who contributed to this + * project. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +#include <common.h> + +/* + * UART test + * + * The controllers are configured to loopback mode and several + * characters are transmitted. + */ + +#ifdef CONFIG_POST + +#include <post.h> + +#if CONFIG_POST & CFG_POST_UART + +#include <asm/processor.h> +#include <serial.h> + +#define UART0_BASE CFG_PERIPHERAL_BASE + 0x00000300 +#define UART1_BASE CFG_PERIPHERAL_BASE + 0x00000400 +#define UART2_BASE CFG_PERIPHERAL_BASE + 0x00000500 +#define UART3_BASE CFG_PERIPHERAL_BASE + 0x00000600 + +#define CR0_MASK 0xdfffffff +#define CR0_EXTCLK_ENA 0x00800000 +#define CR0_UDIV_POS 0 +#define UDIV_SUBTRACT 0 +#define UART0_SDR sdr_uart0 +#define UART1_SDR sdr_uart1 +#define UART2_SDR sdr_uart2 +#define UART3_SDR sdr_uart3 +#define MFREG(a, d) mfsdr(a, d) +#define MTREG(a, d) mtsdr(a, d) + +#define UART_RBR 0x00 +#define UART_THR 0x00 +#define UART_IER 0x01 +#define UART_IIR 0x02 +#define UART_FCR 0x02 +#define UART_LCR 0x03 +#define UART_MCR 0x04 +#define UART_LSR 0x05 +#define UART_MSR 0x06 +#define UART_SCR 0x07 +#define UART_DLL 0x00 +#define UART_DLM 0x01 + +/* + Line Status Register. +*/ +#define asyncLSRDataReady1 0x01 +#define asyncLSROverrunError1 0x02 +#define asyncLSRParityError1 0x04 +#define asyncLSRFramingError1 0x08 +#define asyncLSRBreakInterrupt1 0x10 +#define asyncLSRTxHoldEmpty1 0x20 +#define asyncLSRTxShiftEmpty1 0x40 +#define asyncLSRRxFifoError1 0x80 + +DECLARE_GLOBAL_DATA_PTR; + +static int uart_post_init (unsigned long dev_base) +{ + unsigned long reg; + unsigned long udiv; + unsigned short bdiv; + volatile char val; +#ifdef CFG_EXT_SERIAL_CLOCK + unsigned long tmp; +#endif + int i; + + for (i = 0; i < 3500; i++) { + if (in8 (dev_base + UART_LSR) & asyncLSRTxHoldEmpty1) + break; + udelay (100); + } + MFREG(UART0_SDR, reg); + reg &= ~CR0_MASK; + +#ifdef CFG_EXT_SERIAL_CLOCK + reg |= CR0_EXTCLK_ENA; + udiv = 1; + tmp = gd->baudrate * 16; + bdiv = (CFG_EXT_SERIAL_CLOCK + tmp / 2) / tmp; +#else + /* For 440, the cpu clock is on divider chain A, UART on divider + * chain B ... so cpu clock is irrelevant. Get the "optimized" + * values that are subject to the 1/2 opb clock constraint + */ + serial_divs (gd->baudrate, &udiv, &bdiv); +#endif + + reg |= (udiv - UDIV_SUBTRACT) << CR0_UDIV_POS; /* set the UART divisor */ + + /* + * Configure input clock to baudrate generator for all + * available serial ports here + */ + MTREG(UART0_SDR, reg); +#if defined(UART1_SDR) + MTREG(UART1_SDR, reg); +#endif +#if defined(UART2_SDR) + MTREG(UART2_SDR, reg); +#endif +#if defined(UART3_SDR) + MTREG(UART3_SDR, reg); +#endif + + out8(dev_base + UART_LCR, 0x80); /* set DLAB bit */ + out8(dev_base + UART_DLL, bdiv); /* set baudrate divisor */ + out8(dev_base + UART_DLM, bdiv >> 8); /* set baudrate divisor */ + out8(dev_base + UART_LCR, 0x03); /* clear DLAB; set 8 bits, no parity */ + out8(dev_base + UART_FCR, 0x00); /* disable FIFO */ + out8(dev_base + UART_MCR, 0x10); /* enable loopback mode */ + val = in8(dev_base + UART_LSR); /* clear line status */ + val = in8(dev_base + UART_RBR); /* read receive buffer */ + out8(dev_base + UART_SCR, 0x00); /* set scratchpad */ + out8(dev_base + UART_IER, 0x00); /* set interrupt enable reg */ + + return 0; +} + +static void uart_post_putc (unsigned long dev_base, char c) +{ + int i; + + out8 (dev_base + UART_THR, c); /* put character out */ + + /* Wait for transfer completion */ + for (i = 0; i < 3500; i++) { + if (in8 (dev_base + UART_LSR) & asyncLSRTxHoldEmpty1) + break; + udelay (100); + } +} + +static int uart_post_getc (unsigned long dev_base) +{ + int i; + + /* Wait for character available */ + for (i = 0; i < 3500; i++) { + if (in8 (dev_base + UART_LSR) & asyncLSRDataReady1) + break; + udelay (100); + } + return 0xff & in8 (dev_base + UART_RBR); +} + +static int test_ctlr (unsigned long dev_base, int index) +{ + int res = -1; + char test_str[] = "*** UART Test String ***\r\n"; + int i; + + uart_post_init (dev_base); + + for (i = 0; i < sizeof (test_str) - 1; i++) { + uart_post_putc (dev_base, test_str[i]); + if (uart_post_getc (dev_base) != test_str[i]) + goto done; + } + res = 0; +done: + if (res) + post_log ("uart%d test failed\n", index); + + return res; +} + +int uart_post_test (int flags) +{ + int i, res = 0; + static unsigned long base[] = { + UART0_BASE, UART1_BASE, UART2_BASE, UART3_BASE + }; + + for (i = 0; i < sizeof (base) / sizeof (base[0]); i++) { + if (test_ctlr (base[i], i)) + res = -1; + } + serial_reinit_all (); + + return res; +} + +#endif /* CONFIG_POST & CFG_POST_UART */ + +#endif /* CONFIG_POST */ |