From fcea94ba0773a4bf78d109f2acd72d003f0621f6 Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Fri, 19 Sep 2008 15:50:32 -0700 Subject: [PATCH] ACPI: fix FADT parsing The (1.0 inherited) separate length fields in the FADT are byte granular. Further, PM1a/b may have distinct lengths (if using the v2 fields was okay) and may live in distinct address spaces. acpi_tb_convert_fadt() should account for all of these conditions. Apart from these changes I'm puzzled by the fact that, not just for acpi_gbl_xpm1{a,b}_enable, acpi_hw_low_level_{read,write}() get an explicit size passed rather than using the size found in the passed GAS. What happens on a platform that defines PM1{a,b} wider than 16 bits? Of course, acpi_hw_low_level_{read,write}() at present are entirely un-prepared to deal with sizes other than 8, 16, or 32, not to speak of a non-zero bit_offset or access_width... Signed-off-by: Jan Beulich Signed-off-by: Andrew Morton Signed-off-by: Len Brown --- drivers/acpi/tables/tbfadt.c | 32 +++++++++++++++++++++++++------- 1 file changed, 25 insertions(+), 7 deletions(-) diff --git a/drivers/acpi/tables/tbfadt.c b/drivers/acpi/tables/tbfadt.c index a4a41ba2484b..2c7885e7ffba 100644 --- a/drivers/acpi/tables/tbfadt.c +++ b/drivers/acpi/tables/tbfadt.c @@ -50,7 +50,7 @@ ACPI_MODULE_NAME("tbfadt") /* Local prototypes */ static void inline acpi_tb_init_generic_address(struct acpi_generic_address *generic_address, - u8 bit_width, u64 address); + u8 byte_width, u64 address); static void acpi_tb_convert_fadt(void); @@ -111,7 +111,7 @@ static struct acpi_fadt_info fadt_info_table[] = { * FUNCTION: acpi_tb_init_generic_address * * PARAMETERS: generic_address - GAS struct to be initialized - * bit_width - Width of this register + * byte_width - Width of this register * Address - Address of the register * * RETURN: None @@ -124,7 +124,7 @@ static struct acpi_fadt_info fadt_info_table[] = { static void inline acpi_tb_init_generic_address(struct acpi_generic_address *generic_address, - u8 bit_width, u64 address) + u8 byte_width, u64 address) { /* @@ -136,7 +136,7 @@ acpi_tb_init_generic_address(struct acpi_generic_address *generic_address, /* All other fields are byte-wide */ generic_address->space_id = ACPI_ADR_SPACE_SYSTEM_IO; - generic_address->bit_width = bit_width; + generic_address->bit_width = byte_width << 3; generic_address->bit_offset = 0; generic_address->access_width = 0; } @@ -342,9 +342,20 @@ static void acpi_tb_convert_fadt(void) * useful to calculate them once, here. * * The PM event blocks are split into two register blocks, first is the - * PM Status Register block, followed immediately by the PM Enable Register - * block. Each is of length (pm1_event_length/2) + * PM Status Register block, followed immediately by the PM Enable + * Register block. Each is of length (xpm1x_event_block.bit_width/2). + * + * On various systems the v2 fields (and particularly the bit widths) + * cannot be relied upon, though. Hence resort to using the v1 length + * here (and warn about the inconsistency). */ + if (acpi_gbl_FADT.xpm1a_event_block.bit_width + != acpi_gbl_FADT.pm1_event_length * 8) + printk(KERN_WARNING "FADT: " + "X_PM1a_EVT_BLK.bit_width (%u) does not match" + " PM1_EVT_LEN (%u)\n", + acpi_gbl_FADT.xpm1a_event_block.bit_width, + acpi_gbl_FADT.pm1_event_length); pm1_register_length = (u8) ACPI_DIV_2(acpi_gbl_FADT.pm1_event_length); /* The PM1A register block is required */ @@ -360,13 +371,20 @@ static void acpi_tb_convert_fadt(void) /* The PM1B register block is optional, ignore if not present */ if (acpi_gbl_FADT.xpm1b_event_block.address) { + if (acpi_gbl_FADT.xpm1b_event_block.bit_width + != acpi_gbl_FADT.pm1_event_length * 8) + printk(KERN_WARNING "FADT: " + "X_PM1b_EVT_BLK.bit_width (%u) does not match" + " PM1_EVT_LEN (%u)\n", + acpi_gbl_FADT.xpm1b_event_block.bit_width, + acpi_gbl_FADT.pm1_event_length); acpi_tb_init_generic_address(&acpi_gbl_xpm1b_enable, pm1_register_length, (acpi_gbl_FADT.xpm1b_event_block. address + pm1_register_length)); /* Don't forget to copy space_id of the GAS */ acpi_gbl_xpm1b_enable.space_id = - acpi_gbl_FADT.xpm1a_event_block.space_id; + acpi_gbl_FADT.xpm1b_event_block.space_id; } }