Enhance e820 memory map generation - include files missing from last commit.

3 files changed, 299 insertions, 0 deletions

diff --git a/src/coreboot.c b/src/coreboot.c
new file mode 100644
index 00000000..b0406403
--- /dev/null
+++ b/src/coreboot.c
@@ -0,0 +1,136 @@
+// Coreboot interface support.
+//
+// Copyright (C) 2008  Kevin O'Connor <kevin@koconnor.net>
+//
+// This file may be distributed under the terms of the GNU GPLv3 license.
+
+#include "memmap.h" // add_e820
+#include "util.h" // dprintf
+
+
+/****************************************************************
+ * Memory interface
+ ****************************************************************/
+
+struct cb_header {
+    u32 signature;
+    u32 header_bytes;
+    u32 header_checksum;
+    u32 table_bytes;
+    u32 table_checksum;
+    u32 table_entries;
+};
+
+#define CB_SIGNATURE 0x4f49424C // "LBIO"
+
+struct cb_memory_range {
+    u64 start;
+    u64 size;
+    u32 type;
+};
+
+#define CB_MEM_TABLE    16
+
+struct cb_memory {
+    u32 tag;
+    u32 size;
+    struct cb_memory_range map[0];
+};
+
+#define CB_TAG_MEMORY 0x01
+
+#define MEM_RANGE_COUNT(_rec) \
+        (((_rec)->size - sizeof(*(_rec))) / sizeof((_rec)->map[0]))
+
+static u16
+ipchksum(char *buf, int count)
+{
+    u16 *p = (u16*)buf;
+    u32 sum = 0;
+    while (count > 1) {
+        sum += *p++;
+        count -= 2;
+    }
+    if (count)
+        sum += *(u8*)p;
+    sum = (sum >> 16) + (sum & 0xffff);
+    sum += (sum >> 16);
+    return ~sum;
+}
+
+// Try to locate the coreboot header in a given address range.
+static struct cb_header *
+find_cb_header(char *addr, int len)
+{
+    char *end = addr + len;
+    for (; addr < end; addr += 16) {
+        struct cb_header *cbh = (struct cb_header *)addr;
+        if (cbh->signature != CB_SIGNATURE)
+            continue;
+        dprintf(1, "sig %p=%x\n", addr, cbh->signature);
+        if (! cbh->table_bytes)
+            continue;
+        if (ipchksum(addr, sizeof(*cbh)) != 0)
+            continue;
+        if (ipchksum(addr + sizeof(*cbh), cbh->table_bytes)
+            != cbh->table_checksum)
+            continue;
+        return cbh;
+    }
+    return NULL;
+}
+
+// Try to find the coreboot memory table in the given coreboot table.
+static struct cb_memory *
+find_cb_memory(struct cb_header *cbh)
+{
+    char *tbl = (char *)cbh + sizeof(*cbh);
+    int i;
+    for (i=0; i<cbh->table_entries; i++) {
+        struct cb_memory *cbm = (struct cb_memory *)tbl;
+        tbl += cbm->size;
+        if (cbm->tag == CB_TAG_MEMORY)
+            return cbm;
+    }
+    return NULL;
+}
+
+// Populate max ram and e820 map info by scanning for a coreboot table.
+void
+coreboot_fill_map()
+{
+    dprintf(3, "Attempting to find coreboot table\n");
+    struct cb_header *cbh = find_cb_header(0, 0x1000);
+    if (!cbh)
+        goto fail;
+    struct cb_memory *cbm = find_cb_memory(cbh);
+    if (!cbm)
+        goto fail;
+
+    u64 maxram = 0;
+    int i, count = MEM_RANGE_COUNT(cbm);
+    for (i=0; i<count; i++) {
+        struct cb_memory_range *m = &cbm->map[i];
+        u32 type = m->type;
+        if (type == CB_MEM_TABLE)
+            type = E820_RESERVED;
+        if ((type == E820_ACPI || type == E820_RAM)
+            && (m->start + m->size) > maxram)
+            maxram = m->start + m->size;
+        add_e820(m->start, m->size, type);
+    }
+
+    // Ughh - coreboot likes to set a map at 0x0000-0x1000, but this
+    // confuses grub.  So, override it.
+    add_e820(0, 16*1024, E820_RAM);
+
+    SET_EBDA(ram_size, maxram);
+    return;
+
+fail:
+    // No table found..  Use 16Megs as a dummy value.
+    dprintf(1, "Unable to find coreboot table!\n");
+    SET_EBDA(ram_size, 16*1024*1024);
+    add_e820(0, 16*1024*1024, E820_RAM);
+    return;
+}
diff --git a/src/memmap.c b/src/memmap.c
new file mode 100644
index 00000000..e7ebc2a8
--- /dev/null
+++ b/src/memmap.c
@@ -0,0 +1,138 @@
+// Support for building memory maps suitable for int 15 e820 calls.
+//
+// Copyright (C) 2008  Kevin O'Connor <kevin@koconnor.net>
+//
+// This file may be distributed under the terms of the GNU GPLv3 license.
+
+#include "memmap.h" // struct e820entry
+#include "util.h" // dprintf.h
+
+// Temporary storage used during map building.
+static struct e820entry e820_list[64];
+static int e820_count;
+
+// Remove an entry from the e820_list.
+static void
+remove_e820(int i)
+{
+    e820_count--;
+    memmove(&e820_list[i], &e820_list[i+1]
+            , sizeof(e820_list[0]) * (e820_count - i));
+}
+
+// Insert an entry in the e820_list at the given position.
+static void
+insert_e820(int i, u64 start, u64 size, u32 type)
+{
+    if (e820_count >= ARRAY_SIZE(e820_list)) {
+        dprintf(1, "Overflowed e820 list!\n");
+        return;
+    }
+
+    memmove(&e820_list[i+1], &e820_list[i]
+            , sizeof(e820_list[0]) * (e820_count - i));
+    e820_count++;
+    struct e820entry *e = &e820_list[i];
+    e->start = start;
+    e->size = size;
+    e->type = type;
+}
+
+// Show the current e820_list.
+static void
+dump_map()
+{
+    dprintf(1, "e820 map has %d items:\n", e820_count);
+    int i;
+    for (i=0; i<e820_count; i++) {
+        struct e820entry *e = &e820_list[i];
+        u64 e_end = e->start + e->size;
+        dprintf(1, "  %d: %x%x - %x%x = %d\n", i
+                , (u32)(e->start >> 32), (u32)e->start
+                , (u32)(e_end >> 32), (u32)e_end
+                , e->type);
+    }
+}
+
+// Add a new entry to the list.  This scans for overlaps and keeps the
+// list sorted.
+void
+add_e820(u64 start, u64 size, u32 type)
+{
+    dprintf(8, "Add to e820 map: %x %x %d\n", (u32)start, (u32)size, type);
+
+    if (! size)
+        // Huh?  Nothing to do.
+        return;
+
+    u64 end = start + size;
+    int i;
+    for (i=0; i<e820_count; i++) {
+        struct e820entry *e = &e820_list[i];
+        if (end <= e->start)
+            // Simple insertion point.
+            break;
+        u64 e_end = e->start + e->size;
+        if (start >= e_end)
+            // No overlap.
+            continue;
+        // New item overlaps with an existing one.
+        if (start > e->start) {
+            e->size = start - e->start;
+            i++;
+            if (end < e_end)
+                // Need to split existing item
+                insert_e820(i, end, e_end - end, e->type);
+        }
+        insert_e820(i, start, size, type);
+        i++;
+        // Remove all existing items that are completely overlapped.
+        while (i<e820_count) {
+            e = &e820_list[i];
+            if (end <= e->start)
+                break;
+            e_end = e->start + e->size;
+            if (end < e_end) {
+                // Existing item not completely overlapped - adjust its start.
+                e->start = end;
+                e->size = e_end - e->start;
+                break;
+            }
+            remove_e820(i);
+        }
+        //dump_map();
+        return;
+    }
+    // Just insert item.
+    insert_e820(i, start, size, type);
+    //dump_map();
+}
+
+u32 bios_table_cur_addr, bios_table_end_addr;
+
+// Prep for memmap stuff - init bios table locations.
+void
+memmap_setup()
+{
+    bios_table_cur_addr = 0xf0000 | OFFSET_freespace2_start;
+    bios_table_end_addr = 0xf0000 | OFFSET_freespace2_end;
+    dprintf(1, "bios_table_addr: 0x%08x end=0x%08x\n",
+            bios_table_cur_addr, bios_table_end_addr);
+}
+
+// Copy the temporary e820 map info to its permanent location.
+void
+memmap_finalize()
+{
+    dump_map();
+
+    u32 msize = e820_count * sizeof(e820_list[0]);
+    if (bios_table_cur_addr + msize > bios_table_end_addr) {
+        dprintf(1, "No room for e820 map!\n");
+        return;
+    }
+    memcpy((void*)bios_table_cur_addr, e820_list, msize);
+    SET_EBDA(e820_loc, bios_table_cur_addr);
+    SET_EBDA(e820_count, e820_count);
+    bios_table_cur_addr += msize;
+}
diff --git a/src/memmap.h b/src/memmap.h
new file mode 100644
index 00000000..c0cdca59
--- /dev/null
+++ b/src/memmap.h
@@ -0,0 +1,25 @@
+#ifndef __E820MAP_H
+#define __E820MAP_H
+
+#include "types.h" // u64
+
+#define E820_RAM          1
+#define E820_RESERVED     2
+#define E820_ACPI         3
+#define E820_NVS          4
+#define E820_UNUSABLE     5
+
+struct e820entry {
+    u64 start;
+    u64 size;
+    u32 type;
+};
+
+void add_e820(u64 start, u64 size, u32 type);
+void memmap_setup();
+void memmap_finalize();
+
+// Space for exported bios tables.
+extern u32 bios_table_cur_addr, bios_table_end_addr;
+
+#endif // e820map.h