The existing mechanism is pretty painful as it requires manual
calculations for anything but a trivial setup.
Add a new API for adding e820 entries.
Signed-off-by: Simon Glass <s...@chromium.org>
---
Changes in v3:
- Add new patch with an API for e820
arch/x86/include/asm/e820.h | 87 ++++++++++++++++++++++++++++++++++++-
arch/x86/lib/e820.c | 47 ++++++++++++++++++++
2 files changed, 133 insertions(+), 1 deletion(-)
diff --git a/arch/x86/include/asm/e820.h b/arch/x86/include/asm/e820.h
index cc3758b59fd..a535818b2d5 100644
--- a/arch/x86/include/asm/e820.h
+++ b/arch/x86/include/asm/e820.h
@@ -3,6 +3,8 @@
#define E820MAX 128 /* number of entries in E820MAP */
+#ifdef __ASSEMBLY__
+
#define E820_RAM 1
#define E820_RESERVED 2
#define E820_ACPI 3
@@ -10,9 +12,21 @@
#define E820_UNUSABLE 5
#define E820_COUNT 6 /* Number of types */
-#ifndef __ASSEMBLY__
+#else
+
#include <linux/types.h>
+/* Available e820 memory-region types */
+enum e820_type {
+ E820_RAM = 1,
+ E820_RESERVED,
+ E820_ACPI,
+ E820_NVS,
+ E820_UNUSABLE,
+
+ E820_COUNT,
+};
+
struct e820_entry {
__u64 addr; /* start of memory segment */
__u64 size; /* size of memory segment */
@@ -22,10 +36,81 @@ struct e820_entry {
#define ISA_START_ADDRESS 0xa0000
#define ISA_END_ADDRESS 0x100000
+/**
+ * Context to use for e820_add()
+ *
+ * @entries: Table being filled in
+ * @addr: Current address we are up to
+ * @count: Number of entries added to @entries so far
+ * @max_entries: Maximum number of entries allowed
+ */
+struct e820_ctx {
+ struct e820_entry *entries;
+ u64 addr;
+ int count;
+ int max_entries;
+};
+
+/**
+ * e820_init() - Start setting up an e820 table
+ *
+ * @ctx: Context to set up
+ * @entries: Place to put entries
+ * @max_entries: Maximum size of @entries
+ */
+void e820_init(struct e820_ctx *ctx, struct e820_entry *entries,
+ int max_entries);
+
+/**
+ * e820_add() - Add an entry to the table
+ *
+ * @ctx: Context
+ * @type: Type of entry
+ * @addr: Start address of entry
+ * @size Size of entry
+ */
+void e820_add(struct e820_ctx *ctx, enum e820_type type, u64 addr, u64 size);
+
+/**
+ * e820_to_addr() - Add an entry that covers the space up to a given address
+ *
+ * @ctx: Context
+ * @type: Type of entry
+ * @end_addr: Address where the entry should finish
+ */
+void e820_to_addr(struct e820_ctx *ctx, enum e820_type type, u64 end_addr);
+
+/**
+ * e820_next() - Add an entry that carries on from the last one
+ *
+ * @ctx: Context
+ * @type: Type of entry
+ * @size Size of entry
+ */
+void e820_next(struct e820_ctx *ctx, enum e820_type type, u64 size);
+
+/**
+ * e820_finish() - Finish the table
+ *
+ * Checks the table is not too large, panics if so
+ *
+ * @ctx: Context
+ * Returns: Number of entries
+ */
+int e820_finish(struct e820_ctx *ctx);
+
/* Implementation-defined function to install an e820 map */
unsigned int install_e820_map(unsigned int max_entries,
struct e820_entry *);
+/**
+ * e820_dump() - Dump the e820 table
+ *
+ * @entries: Pointer to start of table
+ * @count: Number of entries in the table
+ */
+void e820_dump(struct e820_entry *entries, uint count);
+
/**
* cb_install_e820_map() - Install e820 map provided by coreboot sysinfo
*
diff --git a/arch/x86/lib/e820.c b/arch/x86/lib/e820.c
index 00ca94776d2..bcc5f6f3044 100644
--- a/arch/x86/lib/e820.c
+++ b/arch/x86/lib/e820.c
@@ -3,8 +3,11 @@
* Copyright (C) 2015, Bin Meng <bmeng...@gmail.com>
*/
+#define LOG_CATEGORY LOGC_ARCH
+
#include <efi_loader.h>
#include <lmb.h>
+#include <log.h>
#include <asm/e820.h>
#include <asm/global_data.h>
@@ -60,6 +63,50 @@ __weak unsigned int install_e820_map(unsigned int
max_entries,
return 4;
}
+void e820_init(struct e820_ctx *ctx, struct e820_entry *entries,
+ int max_entries)
+{
+ memset(ctx, '\0', sizeof(*ctx));
+ ctx->entries = entries;
+ ctx->max_entries = max_entries;
+}
+
+void e820_add(struct e820_ctx *ctx, enum e820_type type, u64 addr, u64 size)
+{
+ struct e820_entry *entry = &ctx->entries[ctx->count++];
+
+ if (ctx->count <= ctx->max_entries) {
+ entry->addr = addr;
+ entry->size = size;
+ entry->type = type;
+ }
+ ctx->addr = addr + size;
+}
+
+void e820_next(struct e820_ctx *ctx, enum e820_type type, u64 size)
+{
+ e820_add(ctx, type, ctx->addr, size);
+}
+
+void e820_to_addr(struct e820_ctx *ctx, enum e820_type type, u64 addr)
+{
+ e820_next(ctx, type, addr - ctx->addr);
+}
+
+int e820_finish(struct e820_ctx *ctx)
+{
+ if (ctx->count > ctx->max_entries) {
+ printf("e820 has %d entries but room for only %d\n", ctx->count,
+ ctx->max_entries);
+ panic("e820 table too large");
+ }
+ log_debug("e820 map installed, n=%d\n", ctx->count);
+ if (_DEBUG)
+ e820_dump(ctx->entries, ctx->count);
+
+ return ctx->count;
+}
+
#if CONFIG_IS_ENABLED(EFI_LOADER)
void efi_add_known_memory(void)
{
--
2.43.0
