u-boot/lib/acpi/base.c
Simon Glass a8efebe719 acpi: Write pointers to tables instead of addresses
Sandbox uses an API to map between addresses and pointers. This allows
it to have (emulated) memory at zero and avoid arch-specific addressing
details. It also allows memory-mapped peripherals to work.

As an example, on many machines sandbox maps address 100 to pointer
value 10000000.

However this is not correct for ACPI, if sandbox starts another program
(e.g EFI app) and passes it the tables. That app has no knowledge of
sandbox's address mapping. So to make this work we want to store
10000000 as the value in the table.

Add two new 'nomap' functions which clearly make this exeption to how
sandbox works.

This should allow EFI apps to access ACPI tables with sandbox, e.g. for
testing purposes.

Signed-off-by: Simon Glass <sjg@chromium.org>
Suggested-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2024-01-07 13:45:07 -07:00

104 lines
2.6 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Write base ACPI tables
*
* Copyright 2021 Google LLC
*/
#define LOG_CATEGORY LOGC_ACPI
#include <acpi/acpi_table.h>
#include <dm/acpi.h>
#include <mapmem.h>
#include <tables_csum.h>
#include <linux/sizes.h>
#include <linux/errno.h>
#include <linux/string.h>
void acpi_write_rsdp(struct acpi_rsdp *rsdp, struct acpi_rsdt *rsdt,
struct acpi_xsdt *xsdt)
{
memset(rsdp, 0, sizeof(struct acpi_rsdp));
memcpy(rsdp->signature, RSDP_SIG, 8);
memcpy(rsdp->oem_id, OEM_ID, 6);
if (rsdt)
rsdp->rsdt_address = nomap_to_sysmem(rsdt);
if (xsdt)
rsdp->xsdt_address = nomap_to_sysmem(xsdt);
rsdp->length = sizeof(struct acpi_rsdp);
rsdp->revision = ACPI_RSDP_REV_ACPI_2_0;
/* Calculate checksums */
rsdp->checksum = table_compute_checksum(rsdp, 20);
rsdp->ext_checksum = table_compute_checksum(rsdp,
sizeof(struct acpi_rsdp));
}
static void acpi_write_rsdt(struct acpi_rsdt *rsdt)
{
struct acpi_table_header *header = &rsdt->header;
/* Fill out header fields */
acpi_fill_header(header, "RSDT");
header->length = sizeof(struct acpi_rsdt);
header->revision = 1;
/* Entries are filled in later, we come with an empty set */
/* Fix checksum */
header->checksum = table_compute_checksum(rsdt,
sizeof(struct acpi_rsdt));
}
static void acpi_write_xsdt(struct acpi_xsdt *xsdt)
{
struct acpi_table_header *header = &xsdt->header;
/* Fill out header fields */
acpi_fill_header(header, "XSDT");
header->length = sizeof(struct acpi_xsdt);
header->revision = 1;
/* Entries are filled in later, we come with an empty set */
/* Fix checksum */
header->checksum = table_compute_checksum(xsdt,
sizeof(struct acpi_xsdt));
}
static int acpi_write_base(struct acpi_ctx *ctx,
const struct acpi_writer *entry)
{
/* We need at least an RSDP and an XSDT Table */
ctx->rsdp = ctx->current;
acpi_inc_align(ctx, sizeof(struct acpi_rsdp));
if (map_to_sysmem(ctx->current) < SZ_4G - SZ_64K) {
ctx->rsdt = ctx->current;
acpi_inc_align(ctx, sizeof(struct acpi_rsdt));
} else {
ctx->rsdt = 0;
}
ctx->xsdt = ctx->current;
acpi_inc_align(ctx, sizeof(struct acpi_xsdt));
/* clear all table memory */
memset(ctx->base, '\0', ctx->current - ctx->base);
acpi_write_rsdp(ctx->rsdp, ctx->rsdt, ctx->xsdt);
if (ctx->rsdt)
acpi_write_rsdt(ctx->rsdt);
acpi_write_xsdt(ctx->xsdt);
return 0;
}
/*
* Per ACPI spec, the FACS table address must be aligned to a 64-byte boundary
* (Windows checks this, but Linux does not).
*
* Use the '0' prefix to put this one first
*/
ACPI_WRITER(0base, NULL, acpi_write_base, ACPIWF_ALIGN64);