/* * udbg for for zilog scc ports as found on Apple PowerMacs * * Copyright (C) 2001-2005 PPC 64 Team, IBM Corp * * 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. */ #include <linux/config.h> #include <linux/types.h> #include <asm/udbg.h> #include <asm/processor.h> #include <asm/naca.h> #include <asm/io.h> #include <asm/prom.h> #include <asm/pmac_feature.h> extern u8 real_readb(volatile u8 __iomem *addr); extern void real_writeb(u8 data, volatile u8 __iomem *addr); #define SCC_TXRDY 4 #define SCC_RXRDY 1 static volatile u8 __iomem *sccc; static volatile u8 __iomem *sccd; static void udbg_scc_putc(unsigned char c) { if (sccc) { while ((in_8(sccc) & SCC_TXRDY) == 0) ; out_8(sccd, c); if (c == '\n') udbg_scc_putc('\r'); } } static int udbg_scc_getc_poll(void) { if (sccc) { if ((in_8(sccc) & SCC_RXRDY) != 0) return in_8(sccd); else return -1; } return -1; } static unsigned char udbg_scc_getc(void) { if (sccc) { while ((in_8(sccc) & SCC_RXRDY) == 0) ; return in_8(sccd); } return 0; } static unsigned char scc_inittab[] = { 13, 0, /* set baud rate divisor */ 12, 0, 14, 1, /* baud rate gen enable, src=rtxc */ 11, 0x50, /* clocks = br gen */ 5, 0xea, /* tx 8 bits, assert DTR & RTS */ 4, 0x46, /* x16 clock, 1 stop */ 3, 0xc1, /* rx enable, 8 bits */ }; void udbg_init_scc(struct device_node *np) { u32 *reg; unsigned long addr; int i, x; if (np == NULL) np = of_find_node_by_name(NULL, "escc"); if (np == NULL || np->parent == NULL) return; udbg_printf("found SCC...\n"); /* Get address within mac-io ASIC */ reg = (u32 *)get_property(np, "reg", NULL); if (reg == NULL) return; addr = reg[0]; udbg_printf("local addr: %lx\n", addr); /* Get address of mac-io PCI itself */ reg = (u32 *)get_property(np->parent, "assigned-addresses", NULL); if (reg == NULL) return; addr += reg[2]; udbg_printf("final addr: %lx\n", addr); /* Setup for 57600 8N1 */ addr += 0x20; sccc = (volatile u8 * __iomem) ioremap(addr & PAGE_MASK, PAGE_SIZE) ; sccc += addr & ~PAGE_MASK; sccd = sccc + 0x10; udbg_printf("ioremap result sccc: %p\n", sccc); mb(); for (i = 20000; i != 0; --i) x = in_8(sccc); out_8(sccc, 0x09); /* reset A or B side */ out_8(sccc, 0xc0); for (i = 0; i < sizeof(scc_inittab); ++i) out_8(sccc, scc_inittab[i]); udbg_putc = udbg_scc_putc; udbg_getc = udbg_scc_getc; udbg_getc_poll = udbg_scc_getc_poll; udbg_puts("Hello World !\n"); } static void udbg_real_scc_putc(unsigned char c) { while ((real_readb(sccc) & SCC_TXRDY) == 0) ; real_writeb(c, sccd); if (c == '\n') udbg_real_scc_putc('\r'); } void udbg_init_pmac_realmode(void) { sccc = (volatile u8 __iomem *)0x80013020ul; sccd = (volatile u8 __iomem *)0x80013030ul; udbg_putc = udbg_real_scc_putc; udbg_getc = NULL; udbg_getc_poll = NULL; }