[PATCH 2/2] lib: fwts_acpi_tables: Force fixup on XSDT and RSDT when loading from .dat files

[IvanHu]

On 07/19/2012 01:49 PM, Colin King wrote:
> From: Colin Ian King <colin.king at canonical.com>
>
> When loading raw ACPI tables from .dat files we have no idea where the original
> .dat tables were in memory, so this means that loading in the XSDT and RSDT is
> problematic because these contain references to the original tables in memory
> but we have no clue how these match up with the raw data.  Since fwts has to
> fake the addresses of the loaded ACPI tables these don't match those in the
> loaded XSDT and RSDT which leads to the ACPICA core getting confused.  The
> best strategy is to therefore not load the XSDT and RSDT and rely on the fwts
> table fix up stage to notice we haven't loaded the XSDT and RSDT and let this
> create these tables based on the tables we have loaded from the raw .dat data,
> leading us to having sane XSDT and RSDT that correctly reference the
> loaded ACPI tables even if they are at faked addresses.
>
> Signed-off-by: Colin Ian King <colin.king at canonical.com>
> ---
>   src/lib/src/fwts_acpi_tables.c |   21 ++++++++++++++++++---
>   1 file changed, 18 insertions(+), 3 deletions(-)
>
> diff --git a/src/lib/src/fwts_acpi_tables.c b/src/lib/src/fwts_acpi_tables.c
> index 4db5844..f388cdd 100644
> --- a/src/lib/src/fwts_acpi_tables.c
> +++ b/src/lib/src/fwts_acpi_tables.c
> @@ -503,9 +503,24 @@ static int fwts_acpi_load_tables_from_file(fwts_framework *fw)
>   						name[4] = '\0';
>   					}
>
> -					fwts_acpi_add_table(name, table,
> -						(uint64_t)fwts_fake_physical_addr(length), length,
> -						FWTS_ACPI_TABLE_FROM_FILE);
> +					if (!strncmp(name, "XSDT", 4) || !strncmp(name, "RSDT", 4)) {
> +						/*
> +						 * For XSDT and RSDT we don't bother loading at this point.
> +						 * These tables point to the other tables, however, we can't
> +						 * figure out which table each pointer references because
> +						 * we are loading in raw table data and we don't know where
> +						 * these were located in the original machine.  So the best
> +						 * way forward is to ignore these tables and instead leave
> +						 * the fix up stage fwts_acpi_load_tables_fixup() to magically
> +						 * create faked XSDT and RSDT entries based on the tables
> +						 * we've loaded from file.
> +						 */
> +						fwts_low_free(table);
> +					} else {
> +						fwts_acpi_add_table(name, table,
> +							(uint64_t)fwts_fake_physical_addr(length), length,
> +							FWTS_ACPI_TABLE_FROM_FILE);
> +					}
>   				}
>   				close(fd);
>   			} else
>
Acked-by: Ivan Hu<ivan.hu at canonical.com>