Initial revision

2 files changed, 569 insertions, 0 deletions

diff --git a/src/firmware/linuxbios/linuxbios.c b/src/firmware/linuxbios/linuxbios.c
new file mode 100644
index 0000000..0ad66dd
--- /dev/null
+++ b/src/firmware/linuxbios/linuxbios.c
@@ -0,0 +1,386 @@
+#ifdef LINUXBIOS
+
+#include "etherboot.h"
+#include "dev.h"
+#include "linuxbios_tables.h"
+
+struct meminfo meminfo;
+static int lb_failsafe = 1;
+static unsigned lb_boot[MAX_BOOT_ENTRIES];
+static unsigned lb_boot_index;
+static struct cmos_entries lb_countdown;
+static struct cmos_checksum lb_checksum;
+
+#undef DEBUG_LINUXBIOS
+
+static void set_base_mem_k(struct meminfo *info, unsigned mem_k)
+{
+	if ((mem_k <= 640) && (info->basememsize <= mem_k)) {
+		info->basememsize = mem_k;
+	}
+}
+static void set_high_mem_k(struct meminfo *info, unsigned mem_k)
+{
+	/* Shave off a megabyte before playing */
+	if (mem_k < 1024) {
+		return;
+	}
+	mem_k -= 1024;
+	if (info->memsize <= mem_k) {
+		info->memsize = mem_k;
+	}
+}
+
+#define for_each_lbrec(head, rec) \
+	for(rec = (struct lb_record *)(((char *)head) + sizeof(*head)); \
+		(((char *)rec) < (((char *)head) + sizeof(*head) + head->table_bytes))  && \
+		(rec->size >= 1) && \
+		((((char *)rec) + rec->size) <= (((char *)head) + sizeof(*head) + head->table_bytes)); \
+		rec = (struct lb_record *)(((char *)rec) + rec->size)) 
+		
+
+#define for_each_crec(tbl, rec) \
+	for(rec = (struct lb_record *)(((char *)tbl) + tbl->header_length); \
+		(((char *)rec) < (((char *)tbl) + tbl->size))  && \
+		(rec->size >= 1) && \
+		((((char *)rec) + rec->size) <= (((char *)tbl) + tbl->size)); \
+		rec = (struct lb_record *)(((char *)rec) + rec->size)) 
+		
+
+
+static void read_lb_memory(
+	struct meminfo *info, struct lb_memory *mem)
+{
+	int i;
+	int entries;
+	entries = (mem->size - sizeof(*mem))/sizeof(mem->map[0]);
+	for(i = 0; (i < entries); i++) {
+		if (info->map_count < E820MAX) {
+			info->map[info->map_count].addr = mem->map[i].start;
+			info->map[info->map_count].size = mem->map[i].size;
+			info->map[info->map_count].type = mem->map[i].type;
+			info->map_count++;
+		}
+		switch(mem->map[i].type) {
+		case LB_MEM_RAM:
+		{
+			unsigned long long end;
+			unsigned long mem_k;
+			end = mem->map[i].start + mem->map[i].size;
+#if defined(DEBUG_LINUXBIOS)
+			printf("lb: %X%X - %X%X (ram)\n",
+				(unsigned long)(mem->map[i].start >>32), 
+				(unsigned long)(mem->map[i].start & 0xFFFFFFFF), 
+				(unsigned long)(end >> 32), 
+				(unsigned long)(end & 0xFFFFFFFF));
+#endif /* DEBUG_LINUXBIOS */
+			end >>= 10;
+			mem_k = end;
+			if (end & 0xFFFFFFFF00000000ULL) {
+				mem_k = 0xFFFFFFFF;
+			}
+			set_base_mem_k(info, mem_k);
+			set_high_mem_k(info, mem_k);
+			break;
+		}
+		case LB_MEM_RESERVED:
+		default:
+#if defined(DEBUG_LINUXBIOS)
+		{
+			unsigned long long end;
+			end = mem->map[i].start + mem->map[i].size;
+			printf("lb: %X%X - %X%X (reserved)\n",
+				(unsigned long)(mem->map[i].start >>32), 
+				(unsigned long)(mem->map[i].start & 0xFFFFFFFF), 
+				(unsigned long)(end >> 32), 
+				(unsigned long)(end & 0xFFFFFFFF));
+		}
+#endif /* DEBUG_LINUXBIOS */
+			break;
+		}
+	}
+}
+
+static unsigned cmos_read(unsigned offset, unsigned int size)
+{
+	unsigned addr, old_addr;
+	unsigned value;
+	
+	addr = offset/8;
+
+	old_addr = inb(0x70);
+	outb(addr | (old_addr &0x80), 0x70);
+	value = inb(0x71);
+	outb(old_addr, 0x70);
+
+	value >>= offset & 0x7;
+	value &= ((1 << size) - 1);
+	
+	return value;
+}
+
+static unsigned cmos_read_checksum(void)
+{
+	unsigned sum = 
+		(cmos_read(lb_checksum.location, 8) << 8) |
+		cmos_read(lb_checksum.location +8, 8);
+	return sum & 0xffff;
+}
+
+static int cmos_valid(void)
+{
+	unsigned i;
+	unsigned sum, old_sum;
+	sum = 0;
+	if ((lb_checksum.tag != LB_TAG_OPTION_CHECKSUM) || 
+		(lb_checksum.type != CHECKSUM_PCBIOS) ||
+		(lb_checksum.size != sizeof(lb_checksum))) {
+		return 0;
+	}
+	for(i = lb_checksum.range_start; i <= lb_checksum.range_end; i+= 8) {
+		sum += cmos_read(i, 8);
+	}
+	sum = (~sum)&0x0ffff;
+	old_sum = cmos_read_checksum();
+	return sum == old_sum;
+}
+
+static void cmos_write(unsigned offset, unsigned int size, unsigned setting)
+{
+	unsigned addr, old_addr;
+	unsigned value, mask, shift;
+	unsigned sum;
+	
+	addr = offset/8;
+	
+	shift = offset & 0x7;
+	mask = ((1 << size) - 1) << shift;
+	setting = (setting << shift) & mask;
+
+	old_addr = inb(0x70);
+	sum = cmos_read_checksum();
+	sum = (~sum) & 0xffff;
+
+	outb(addr | (old_addr &0x80), 0x70);
+	value = inb(0x71);
+	sum -= value;
+	value &= ~mask;
+	value |= setting;
+	sum += value;
+	outb(value, 0x71);
+
+	sum = (~sum) & 0x0ffff;
+	outb((lb_checksum.location/8) | (old_addr & 0x80), 0x70);
+	outb((sum >> 8) & 0xff, 0x71);
+	outb(((lb_checksum.location +8)/8) | (old_addr & 0x80), 0x70);
+	outb(sum & 0xff, 0x71);
+
+	outb(old_addr, 0x70);
+
+	return;
+}
+
+static void read_linuxbios_values(struct meminfo *info,
+	struct lb_header *head)
+{
+	/* Read linuxbios tables... */
+	struct lb_record *rec;
+	memset(lb_boot, 0, sizeof(lb_boot));
+	for_each_lbrec(head, rec) {
+		switch(rec->tag) {
+		case LB_TAG_MEMORY:
+		{
+			struct lb_memory *mem;
+			mem = (struct lb_memory *) rec;
+			read_lb_memory(info, mem); 
+			break;
+		}
+		case LB_TAG_CMOS_OPTION_TABLE:
+		{
+			struct cmos_option_table *tbl;
+			struct lb_record *crec;
+			struct cmos_entries *entry;
+			tbl = (struct cmos_option_table *)rec;
+			for_each_crec(tbl, crec) {
+				/* Pick off the checksum entry and keep it */
+				if (crec->tag == LB_TAG_OPTION_CHECKSUM) {
+					memcpy(&lb_checksum, crec, sizeof(lb_checksum));
+					continue;
+				}
+				if (crec->tag != LB_TAG_OPTION)
+					continue;
+				entry = (struct cmos_entries *)crec;
+				if ((entry->bit < 112) || (entry->bit > 1020))
+					continue;
+				/* See if LinuxBIOS came up in fallback or normal mode */
+				if (memcmp(entry->name, "last_boot", 10) == 0) {
+					lb_failsafe = cmos_read(entry->bit, entry->length) == 0;
+					continue;
+				}
+				/* Find where the boot countdown is */
+				if (memcmp(entry->name, "boot_countdown", 15) == 0) {
+					lb_countdown =  *entry;
+					continue;
+				}
+				/* Find the default boot index */
+				if (memcmp(entry->name, "boot_index", 11) == 0) {
+					lb_boot_index = cmos_read(entry->bit, entry->length);
+					continue;
+				}
+				/* Now filter for the boot order options */
+				if (entry->length != 4)
+					continue;
+				if (entry->config != 'e')
+					continue;
+				if (memcmp(entry->name, "boot_first", 11) == 0) {
+					lb_boot[0] = cmos_read(entry->bit, entry->length);
+				}
+				else if (memcmp(entry->name, "boot_second", 12) == 0) {
+					lb_boot[1] = cmos_read(entry->bit, entry->length);
+				}
+				else if (memcmp(entry->name, "boot_third", 11) == 0) {
+					lb_boot[2] = cmos_read(entry->bit, entry->length);
+				}
+			}
+			break;
+		}
+		default: 
+			break;
+		};
+	}
+}
+
+
+
+static unsigned long count_lb_records(void *start, unsigned long length)
+{
+	struct lb_record *rec;
+	void *end;
+	unsigned long count;
+	count = 0;
+	end = ((char *)start) + length;
+	for(rec = start; ((void *)rec < end) &&
+		((signed long)rec->size <= (end - (void *)rec)); 
+		rec = (void *)(((char *)rec) + rec->size)) {
+		count++;
+	}
+	return count;
+}
+
+static int find_lb_table(void *start, void *end, struct lb_header **result)
+{
+	unsigned char *ptr;
+
+	/* For now be stupid.... */
+	for(ptr = start; virt_to_phys(ptr) < virt_to_phys(end); ptr += 16) {
+		struct lb_header *head = (struct lb_header *)ptr;
+		if (	(head->signature[0] != 'L') || 
+			(head->signature[1] != 'B') ||
+			(head->signature[2] != 'I') ||
+			(head->signature[3] != 'O')) {
+			continue;
+		}
+		if (head->header_bytes != sizeof(*head))
+			continue;
+#if defined(DEBUG_LINUXBIOS)
+		printf("Found canidate at: %X\n", virt_to_phys(head));
+#endif
+		if (ipchksum((uint16_t *)head, sizeof(*head)) != 0) 
+			continue;
+#if defined(DEBUG_LINUXBIOS)
+		printf("header checksum o.k.\n");
+#endif
+		if (ipchksum((uint16_t *)(ptr + sizeof(*head)), head->table_bytes) !=
+			head->table_checksum) {
+			continue;
+		}
+#if defined(DEBUG_LINUXBIOS)
+		printf("table checksum o.k.\n");
+#endif
+		if (count_lb_records(ptr + sizeof(*head), head->table_bytes) !=
+			head->table_entries) {
+			continue;
+		}
+#if defined(DEBUG_LINUXBIOS)
+		printf("record count o.k.\n");
+#endif
+		*result = head;
+		return 1;
+	};
+	return 0;
+}
+
+void get_memsizes(void)
+{
+	struct lb_header *lb_table;
+	int found;
+#if defined(DEBUG_LINUXBIOS)
+	printf("\nSearching for linuxbios tables...\n");
+#endif /* DEBUG_LINUXBIOS */
+	found = 0;
+	meminfo.basememsize = 0;
+	meminfo.memsize = 0;
+	meminfo.map_count = 0;
+	/* This code is specific to linuxBIOS but could
+	 * concievably be extended to work under a normal bios.
+	 * but size is important...
+	 */
+	if (!found) {
+		found = find_lb_table(phys_to_virt(0x00000), phys_to_virt(0x01000), &lb_table);
+	}
+	if (!found) {
+		found = find_lb_table(phys_to_virt(0xf0000), phys_to_virt(0x100000), &lb_table);
+	}
+	if (found) {
+#if defined (DEBUG_LINUXBIOS)
+		printf("Found LinuxBIOS table at: %X\n", virt_to_phys(lb_table));
+#endif
+		read_linuxbios_values(&meminfo, lb_table);
+	}
+
+#if defined(DEBUG_LINUXBIOS)
+	printf("base_mem_k = %d high_mem_k = %d\n", 
+		meminfo.basememsize, meminfo.memsize);
+#endif /* DEBUG_LINUXBIOS */
+	
+}
+
+unsigned long get_boot_order(unsigned long order, unsigned *index)
+{
+	static int again;
+	static int checksum_valid;
+	static unsigned boot_count;
+	int i;
+
+	if (!lb_failsafe && !again) {
+		/* Decrement the boot countdown the first time through */
+		checksum_valid = cmos_valid();
+		boot_count = cmos_read(lb_countdown.bit, lb_countdown.length);
+		if (boot_count > 0) {
+			cmos_write(lb_countdown.bit, lb_countdown.length, boot_count -1);
+		}
+		again = 1;
+	}
+	if (lb_failsafe || !checksum_valid) {
+		/* When LinuxBIOS is in failsafe mode, or there is an
+		 * invalid cmos checksum ignore all cmos options 
+		 */
+		return order;
+	}
+	for(i = 0; i < MAX_BOOT_ENTRIES; i++) {
+		unsigned long boot;
+		boot = order >> (i*BOOT_BITS) & BOOT_MASK;
+		boot = lb_boot[i] & BOOT_TYPE_MASK;
+		if (boot >= BOOT_NOTHING) {
+			boot = BOOT_NOTHING;
+		}
+		if (boot_count == 0) {
+			boot |= BOOT_FAILSAFE;
+		}
+		order &= ~(BOOT_MASK << (i * BOOT_BITS));
+		order |= (boot << (i*BOOT_BITS));
+	}
+	*index = lb_boot_index;
+	return order;
+}
+#endif /* LINUXBIOS */
diff --git a/src/firmware/linuxbios/linuxbios_tables.h b/src/firmware/linuxbios/linuxbios_tables.h
new file mode 100644
index 0000000..ee21520
--- /dev/null
+++ b/src/firmware/linuxbios/linuxbios_tables.h
@@ -0,0 +1,183 @@
+#ifndef LINUXBIOS_TABLES_H
+#define LINUXBIOS_TABLES_H
+
+#include "stdint.h"
+
+/* The linuxbios table information is for conveying information
+ * from the firmware to the loaded OS image.  Primarily this
+ * is expected to be information that cannot be discovered by
+ * other means, such as quering the hardware directly.
+ *
+ * All of the information should be Position Independent Data.  
+ * That is it should be safe to relocated any of the information
+ * without it's meaning/correctnes changing.   For table that
+ * can reasonably be used on multiple architectures the data
+ * size should be fixed.  This should ease the transition between
+ * 32 bit and 64 bit architectures etc.
+ *
+ * The completeness test for the information in this table is:
+ * - Can all of the hardware be detected?
+ * - Are the per motherboard constants available?
+ * - Is there enough to allow a kernel to run that was written before
+ *   a particular motherboard is constructed? (Assuming the kernel
+ *   has drivers for all of the hardware but it does not have
+ *   assumptions on how the hardware is connected together).
+ *
+ * With this test it should be straight forward to determine if a
+ * table entry is required or not.  This should remove much of the
+ * long term compatibility burden as table entries which are
+ * irrelevant or have been replaced by better alternatives may be
+ * dropped.  Of course it is polite and expidite to include extra
+ * table entries and be backwards compatible, but it is not required.
+ */
+
+
+struct lb_header
+{
+	uint8_t  signature[4]; /* LBIO */
+	uint32_t header_bytes;
+	uint32_t header_checksum;
+	uint32_t table_bytes;
+	uint32_t table_checksum;
+	uint32_t table_entries;
+};
+
+/* Every entry in the boot enviroment list will correspond to a boot
+ * info record.  Encoding both type and size.  The type is obviously
+ * so you can tell what it is.  The size allows you to skip that
+ * boot enviroment record if you don't know what it easy.  This allows
+ * forward compatibility with records not yet defined.
+ */
+struct lb_record {
+	uint32_t tag;		/* tag ID */
+	uint32_t size;		/* size of record (in bytes) */
+};
+
+#define LB_TAG_UNUSED	0x0000
+
+#define LB_TAG_MEMORY	0x0001
+
+struct lb_memory_range {
+	uint64_t start;
+	uint64_t size;
+	uint32_t type;
+#define LB_MEM_RAM       1	/* Memory anyone can use */
+#define LB_MEM_RESERVED  2	/* Don't use this memory region */
+#define LB_MEM_TABLE     16	/* Ram configuration tables are kept in */
+	
+};
+
+struct lb_memory {
+	uint32_t tag;
+	uint32_t size;
+	struct lb_memory_range map[0];
+};
+
+#define LB_TAG_HWRPB	0x0002
+struct lb_hwrpb {
+	uint32_t tag;
+	uint32_t size;
+	uint64_t hwrpb;
+};
+
+#define LB_TAG_MAINBOARD	0x0003
+struct lb_mainboard {
+	uint32_t tag;
+	uint32_t size;
+	uint8_t  vendor_idx;
+	uint8_t  part_number_idx;
+	uint8_t  strings[0];
+};
+
+#define LB_TAG_VERSION		0x0004
+#define LB_TAG_EXTRA_VERSION	0x0005
+#define LB_TAG_BUILD		0x0006
+#define LB_TAG_COMPILE_TIME	0x0007
+#define LB_TAG_COMPILE_BY	0x0008
+#define LB_TAG_COMPILE_HOST	0x0009
+#define LB_TAG_COMPILE_DOMAIN	0x000a
+#define LB_TAG_COMPILER		0x000b
+#define LB_TAG_LINKER		0x000c
+#define LB_TAG_ASSEMBLER	0x000d
+struct lb_string {
+	uint32_t tag;
+	uint32_t size;
+	uint8_t  string[0];
+};
+
+/* The following structures are for the cmos definitions table */
+#define LB_TAG_CMOS_OPTION_TABLE 200
+/* cmos header record */
+struct cmos_option_table {
+	uint32_t tag;               /* CMOS definitions table type */
+	uint32_t size;               /* size of the entire table */
+	uint32_t header_length;      /* length of header */
+};
+
+/* cmos entry record
+        This record is variable length.  The name field may be
+        shorter than CMOS_MAX_NAME_LENGTH. The entry may start
+        anywhere in the byte, but can not span bytes unless it
+        starts at the beginning of the byte and the length is
+        fills complete bytes.
+*/
+#define LB_TAG_OPTION 201
+struct cmos_entries {
+	uint32_t tag;                /* entry type */
+	uint32_t size;               /* length of this record */
+	uint32_t bit;                /* starting bit from start of image */
+	uint32_t length;             /* length of field in bits */
+	uint32_t config;             /* e=enumeration, h=hex, r=reserved */
+	uint32_t config_id;          /* a number linking to an enumeration record */
+#define CMOS_MAX_NAME_LENGTH 32
+	uint8_t name[CMOS_MAX_NAME_LENGTH]; /* name of entry in ascii, 
+					       variable length int aligned */
+};
+
+
+/* cmos enumerations record
+        This record is variable length.  The text field may be
+        shorter than CMOS_MAX_TEXT_LENGTH.
+*/
+#define LB_TAG_OPTION_ENUM 202
+struct cmos_enums {
+	uint32_t tag;		     /* enumeration type */
+	uint32_t size; 		     /* length of this record */
+	uint32_t config_id;          /* a number identifying the config id */
+	uint32_t value;              /* the value associated with the text */
+#define CMOS_MAX_TEXT_LENGTH 32
+	uint8_t text[CMOS_MAX_TEXT_LENGTH]; /* enum description in ascii, 
+						variable length int aligned */
+};
+
+/* cmos defaults record
+        This record contains default settings for the cmos ram.
+*/
+#define LB_TAG_OPTION_DEFAULTS 203
+struct cmos_defaults {
+	uint32_t tag;                /* default type */
+	uint32_t size;               /* length of this record */
+	uint32_t name_length;        /* length of the following name field */
+	uint8_t name[CMOS_MAX_NAME_LENGTH]; /* name identifying the default */
+#define CMOS_IMAGE_BUFFER_SIZE 128
+	uint8_t default_set[CMOS_IMAGE_BUFFER_SIZE]; /* default settings */
+};
+
+#define LB_TAG_OPTION_CHECKSUM 204
+struct	cmos_checksum {
+	uint32_t tag;
+	uint32_t size;
+	/* In practice everything is byte aligned, but things are measured
+	 * in bits to be consistent.
+	 */
+	uint32_t range_start;	/* First bit that is checksummed (byte aligned) */
+	uint32_t range_end;	/* Last bit that is checksummed (byte aligned) */
+	uint32_t location;	/* First bit of the checksum (byte aligned) */
+	uint32_t type;		/* Checksum algorithm that is used */
+#define CHECKSUM_NONE	0
+#define CHECKSUM_PCBIOS	1
+};
+
+
+
+#endif /* LINUXBIOS_TABLES_H */