* Patch by Daniel Engström, 13 Nov 2002:
  Add support for i386 architecture and AMD SC520 board

* Patch by Pierre Aubert, 12 Nov 2002:
  Add support for DOS filesystem and booting from DOS floppy disk
diff --git a/lib_i386/ic/sc520.c b/lib_i386/ic/sc520.c
new file mode 100644
index 0000000..d202625
--- /dev/null
+++ b/lib_i386/ic/sc520.c
@@ -0,0 +1,348 @@
+/*
+ * (C) Copyright 2002
+ * Daniel Engström, Omicron Ceti AB <daniel@omicron.se>.
+ *
+ * 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
+ */
+
+/* stuff specific for the sc520,
+ * but idependent of implementation */
+
+
+#include <common.h>
+#include <config.h>
+#include <pci.h>
+#include <asm/io.h>
+#include <asm/pci.h>
+#include <asm/ic/sc520.h>
+
+/* 
+ * utility functions for boards based on the AMD sc520 
+ * 
+ * void write_mmcr_byte(u16 mmcr, u8 data)
+ * void write_mmcr_word(u16 mmcr, u16 data)
+ * void write_mmcr_long(u16 mmcr, u32 data)
+ * 
+ * u8   read_mmcr_byte(u16 mmcr)
+ * u16  read_mmcr_word(u16 mmcr)
+ * u32  read_mmcr_long(u16 mmcr)
+ * 
+ * void init_sc520(void)
+ * unsigned long init_sc520_dram(void)
+ * void pci_sc520_init(struct pci_controller *hose)
+ * 
+ * void reset_timer(void)
+ * ulong get_timer(ulong base)
+ * void set_timer(ulong t)
+ * void udelay(unsigned long usec)
+ * 
+ */
+
+static u32 mmcr_base= 0xfffef000;
+
+void write_mmcr_byte(u16 mmcr, u8 data)
+{
+	writeb(data, mmcr+mmcr_base);
+}
+
+void write_mmcr_word(u16 mmcr, u16 data)
+{
+	writew(data, mmcr+mmcr_base);	
+}
+
+void write_mmcr_long(u16 mmcr, u32 data)
+{
+	writel(data, mmcr+mmcr_base);
+}
+
+u8 read_mmcr_byte(u16 mmcr)
+{
+	return readb(mmcr+mmcr_base);
+}
+
+u16 read_mmcr_word(u16 mmcr)
+{
+	return readw(mmcr+mmcr_base);	
+}
+
+u32 read_mmcr_long(u16 mmcr)
+{
+	return readl(mmcr+mmcr_base);
+}
+
+
+void init_sc520(void)
+{
+	DECLARE_GLOBAL_DATA_PTR;
+	
+	/* Set the UARTxCTL register at it's slower,
+	 * baud clock giving us a 1.8432 MHz reference 
+	 */
+	write_mmcr_byte(SC520_UART1CTL, 7);
+	write_mmcr_byte(SC520_UART2CTL, 7);
+	
+	/* first set the timer pin mapping */
+	write_mmcr_byte(SC520_CLKSEL, 0x72);	/* no clock frequency selected, use 1.1892MHz */
+	
+	/* enable PCI bus arbitrer */
+	write_mmcr_byte(SC520_SYSARBCTL,0x02);  /* enable concurrent mode */
+	
+	write_mmcr_word(SC520_SYSARBMENB,0x1f); /* enable external grants */
+	write_mmcr_word(SC520_HBCTL,0x04);      /* enable posted-writes */
+
+
+	if (CFG_SC520_HIGH_SPEED) {
+		write_mmcr_byte(SC520_CPUCTL, 0x2);	/* set it to 133 MHz and write back */
+		gd->cpu_clk = 133000000;
+		printf("## CPU Speed set to 133MHz\n");
+	} else {
+		write_mmcr_byte(SC520_CPUCTL, 1);	/* set CPU to 100 MHz and write back cache */
+		printf("## CPU Speed set to 100MHz\n");
+		gd->cpu_clk = 100000000;
+	}
+	
+
+	/* wait at least one millisecond */
+        asm("movl	$0x2000,%%ecx\n"
+	    "wait_loop:	pushl %%ecx\n"
+	    "popl	%%ecx\n"
+	    "loop wait_loop\n": : : "ecx");
+
+	/* turn on the SDRAM write buffer */
+	write_mmcr_byte(SC520_DBCTL, 0x11);
+
+	/* turn on the cache and disable write through */
+	asm("movl	%%cr0, %%eax\n"
+	    "andl	$0x9fffffff, %%eax\n"
+	    "movl	%%eax, %%cr0\n"  : : : "eax");
+}
+
+unsigned long init_sc520_dram(void)
+{
+	DECLARE_GLOBAL_DATA_PTR;
+	bd_t *bd = gd->bd;
+	
+	u32 dram_present=0;
+	u32 dram_ctrl;
+
+	int val;
+	
+	int cas_precharge_delay = CFG_SDRAM_PRECHARGE_DELAY;	
+	int refresh_rate        = CFG_SDRAM_REFRESH_RATE;	
+	int ras_cas_delay       = CFG_SDRAM_RAS_CAS_DELAY;
+	
+	/* set SDRAM speed here */
+	
+	refresh_rate/=78;	
+	if (refresh_rate<=1) {
+		val = 0;  /* 7.8us */
+	} else if (refresh_rate==2) {
+		val = 1;  /* 15.6us */
+	} else if (refresh_rate==3 || refresh_rate==4) {
+		val = 2;  /* 31.2us */
+	} else {
+		val = 3;  /* 62.4us */
+	}
+	write_mmcr_byte(SC520_DRCCTL, (read_mmcr_byte(SC520_DRCCTL) & 0xcf) | (val<<4));
+	
+	val = read_mmcr_byte(SC520_DRCTMCTL);
+	val &= 0xf0;
+	
+	if (cas_precharge_delay==3) {		
+		val |= 0x04;   /* 3T */
+	} else if (cas_precharge_delay==4) {		
+		val |= 0x08;   /* 4T */
+	} else if (cas_precharge_delay>4) {		
+		val |= 0x0c;
+	} 
+	
+	if (ras_cas_delay > 3) {
+		val |= 2; 
+	} else {
+		val |= 1; 
+	}
+	write_mmcr_byte(SC520_DRCTMCTL, val);
+
+
+	/* We read-back the configuration of the dram
+	 * controller that the assembly code wrote */
+	dram_ctrl = read_mmcr_long(SC520_DRCBENDADR);
+	
+
+	bd->bi_dram[0].start = 0;
+	if (dram_ctrl & 0x80) {
+		/* bank 0 enabled */
+		dram_present = bd->bi_dram[1].start = (dram_ctrl & 0x7f) << 22;
+		bd->bi_dram[0].size = bd->bi_dram[1].start; 
+
+	} else {
+		bd->bi_dram[0].size = 0;
+		bd->bi_dram[1].start = bd->bi_dram[0].start;
+	}
+	
+	if (dram_ctrl & 0x8000) {
+		/* bank 1 enabled */
+		dram_present = bd->bi_dram[2].start = (dram_ctrl & 0x7f00) << 14;
+		bd->bi_dram[1].size = bd->bi_dram[2].start -  bd->bi_dram[1].start; 
+	} else {
+		bd->bi_dram[1].size = 0;
+		bd->bi_dram[2].start = bd->bi_dram[1].start;
+	}
+	
+	if (dram_ctrl & 0x800000) {
+		/* bank 2 enabled */
+		dram_present = bd->bi_dram[3].start = (dram_ctrl & 0x7f0000) << 6;
+		bd->bi_dram[2].size = bd->bi_dram[3].start -  bd->bi_dram[2].start; 
+	} else {
+		bd->bi_dram[2].size = 0;
+		bd->bi_dram[3].start = bd->bi_dram[2].start;
+	} 
+	
+	if (dram_ctrl & 0x80000000) {
+		/* bank 3 enabled */
+		dram_present  = (dram_ctrl & 0x7f000000) >> 2;
+		bd->bi_dram[3].size = dram_present -  bd->bi_dram[3].start;
+	} else {
+		bd->bi_dram[3].size = 0;
+	}
+
+	
+#if 0	
+	printf("Configured %d bytes of dram\n", dram_present);
+#endif	
+	gd->ram_size = dram_present;
+	
+	return dram_present;
+}
+
+
+#ifdef CONFIG_PCI
+
+
+
+void pci_sc520_init(struct pci_controller *hose)
+{
+	hose->first_busno = 0;
+	hose->last_busno = 0xff;
+
+	/* System memory space */
+	pci_set_region(hose->regions + 0, 
+		       SC520_PCI_MEMORY_BUS,
+		       SC520_PCI_MEMORY_PHYS,
+		       SC520_PCI_MEMORY_SIZE,
+		       PCI_REGION_MEM | PCI_REGION_MEMORY);
+
+	/* PCI memory space */
+	pci_set_region(hose->regions + 1, 
+		       SC520_PCI_MEM_BUS,
+		       SC520_PCI_MEM_PHYS,
+		       SC520_PCI_MEM_SIZE,
+		       PCI_REGION_MEM);
+
+	/* ISA/PCI memory space */
+	pci_set_region(hose->regions + 2, 
+		       SC520_ISA_MEM_BUS,
+		       SC520_ISA_MEM_PHYS,
+		       SC520_ISA_MEM_SIZE,
+		       PCI_REGION_MEM);
+
+	/* PCI I/O space */
+	pci_set_region(hose->regions + 3, 
+		       SC520_PCI_IO_BUS,
+		       SC520_PCI_IO_PHYS,
+		       SC520_PCI_IO_SIZE,
+		       PCI_REGION_IO);
+
+	/* ISA/PCI I/O space */
+	pci_set_region(hose->regions + 4, 
+		       SC520_ISA_IO_BUS,
+		       SC520_ISA_IO_PHYS,
+		       SC520_ISA_IO_SIZE,
+		       PCI_REGION_IO);
+
+	hose->region_count = 5;
+
+	pci_setup_type1(hose,
+			SC520_REG_ADDR,
+			SC520_REG_DATA);
+
+	pci_register_hose(hose);
+
+	hose->last_busno = pci_hose_scan(hose);
+	
+	/* enable target memory acceses on host brige */
+	pci_write_config_word(0, PCI_COMMAND, 
+			      PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER);
+
+}
+
+
+#endif
+
+#ifdef CFG_TIMER_SC520
+
+
+void reset_timer(void)
+{
+	write_mmcr_word(SC520_GPTMR0CNT, 0);
+	write_mmcr_word(SC520_GPTMR0CTL, 0x6001);
+	
+}
+
+ulong get_timer(ulong base)
+{
+	/* fixme: 30 or 33 */
+	return 	read_mmcr_word(SC520_GPTMR0CNT) / 33;
+}
+
+void set_timer(ulong t)
+{
+	/* FixMe: use two cascade coupled timers */
+	write_mmcr_word(SC520_GPTMR0CTL, 0x4001);
+	write_mmcr_word(SC520_GPTMR0CNT, t*33);
+	write_mmcr_word(SC520_GPTMR0CTL, 0x6001);
+}
+
+
+void udelay(unsigned long usec)
+{
+	int m=0;
+	long u;
+	
+	read_mmcr_word(SC520_SWTMRMILLI);
+	read_mmcr_word(SC520_SWTMRMICRO);
+	     
+#if 0
+	/* do not enable this line, udelay is used in the serial driver -> recursion */
+	printf("udelay: %ld m.u %d.%d  tm.tu %d.%d\n", usec, m, u, tm, tu);
+#endif	
+	while (1) {
+		
+		m += read_mmcr_word(SC520_SWTMRMILLI);
+		u = read_mmcr_word(SC520_SWTMRMICRO) + (m * 1000);
+		
+		if (usec <= u) {
+			break;
+		}
+	}
+}
+
+#endif
+
+