[PATCH v2 19/30] x86: acpi: Put the generated code first in DSDT

[Simon Glass]

The current implementation for DSDT tables is not correct for the case
where there is generated code, as the length ends up being incorrect.
Also, we want the generated code to go first in the table.

Rewrite this piece to correct these problems.

Signed-off-by: Simon Glass <sjg at chromium.org>
Reviewed-by: Bin Meng <bmeng.cn at gmail.com>
---

(no changes since v1)

 arch/x86/lib/acpi_table.c | 27 ++++++++++++++++++---------
 1 file changed, 18 insertions(+), 9 deletions(-)

diff --git a/arch/x86/lib/acpi_table.c b/arch/x86/lib/acpi_table.c
index c5c5c6e6794..423df5cbf9b 100644
--- a/arch/x86/lib/acpi_table.c
+++ b/arch/x86/lib/acpi_table.c
@@ -505,6 +505,7 @@ static int acpi_create_ssdt(struct acpi_ctx *ctx,
  */
 ulong write_acpi_tables(ulong start_addr)
 {
+	const int thl = sizeof(struct acpi_table_header);
 	struct acpi_ctx *ctx;
 	struct acpi_facs *facs;
 	struct acpi_table_header *dsdt;
@@ -516,6 +517,7 @@ ulong write_acpi_tables(ulong start_addr)
 	struct acpi_csrt *csrt;
 	struct acpi_spcr *spcr;
 	void *start;
+	int aml_len;
 	ulong addr;
 	int ret;
 	int i;
@@ -541,21 +543,28 @@ ulong write_acpi_tables(ulong start_addr)
 	dsdt = ctx->current;
 
 	/* Put the table header first */
-	memcpy(dsdt, &AmlCode, sizeof(struct acpi_table_header));
-	acpi_inc(ctx, sizeof(struct acpi_table_header));
+	memcpy(dsdt, &AmlCode, thl);
+	acpi_inc(ctx, thl);
+	log_debug("DSDT starts at %p, hdr ends at %p\n", dsdt, ctx->current);
 
 	/* If the table is not empty, allow devices to inject things */
-	if (dsdt->length >= sizeof(struct acpi_table_header))
-		acpi_inject_dsdt(ctx);
+	aml_len = dsdt->length - thl;
+	if (aml_len) {
+		void *base = ctx->current;
 
-	/* Copy in the AML code itself if any (after the header) */
-	memcpy(ctx->current,
-	       (char *)&AmlCode + sizeof(struct acpi_table_header),
-	       dsdt->length - sizeof(struct acpi_table_header));
+		acpi_inject_dsdt(ctx);
+		log_debug("Added %x bytes from inject_dsdt, now at %p\n",
+			  ctx->current - base, ctx->current);
+		log_debug("Copy AML code size %x to %p\n", aml_len,
+			  ctx->current);
+		memcpy(ctx->current, AmlCode + thl, aml_len);
+		acpi_inc(ctx, aml_len);
+	}
 
-	acpi_inc(ctx, dsdt->length - sizeof(struct acpi_table_header));
 	dsdt->length = ctx->current - (void *)dsdt;
 	acpi_align(ctx);
+	log_debug("Updated DSDT length to %x, total %x\n", dsdt->length,
+		  ctx->current - (void *)dsdt);
 
 	if (!IS_ENABLED(CONFIG_ACPI_GNVS_EXTERNAL)) {
 		/* Pack GNVS into the ACPI table area */
-- 
2.29.0.rc1.297.gfa9743e501-goog