ACPICA: FADT: set acpi_gbl_use_default_register_widths to TRUE by default

This returns the FADT support to the original behavior, which is
to use default register widths. However, now check each register
definition and report a warning if it differs from the default.
This is a first step to moving away from the default widths,
rather than outright believing the widths in all FADTs for all
machines, considered rather dangerous until more data is obtained.

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 105 insertions, 68 deletions

diff --git a/drivers/acpi/tables/tbfadt.c b/drivers/acpi/tables/tbfadt.c
index b4ce2074c91f..7dec0af3f26a 100644
--- a/drivers/acpi/tables/tbfadt.c
+++ b/drivers/acpi/tables/tbfadt.c
@@ -61,9 +61,10 @@ static void acpi_tb_validate_fadt(void);
 
 typedef struct acpi_fadt_info {
         char *name;
-        u8 target;
-        u8 source;
+        u8 address64;
+        u8 address32;
         u8 length;
+        u8 default_length;
         u8 type;
 
 } acpi_fadt_info;
@@ -72,37 +73,61 @@ typedef struct acpi_fadt_info {
 #define ACPI_FADT_SEPARATE_LENGTH   2
 
 static struct acpi_fadt_info fadt_info_table[] = {
-        {"Pm1aEventBlock", ACPI_FADT_OFFSET(xpm1a_event_block),
+        {"Pm1aEventBlock",
+         ACPI_FADT_OFFSET(xpm1a_event_block),
          ACPI_FADT_OFFSET(pm1a_event_block),
-         ACPI_FADT_OFFSET(pm1_event_length), ACPI_FADT_REQUIRED},
+         ACPI_FADT_OFFSET(pm1_event_length),
+         ACPI_PM1_REGISTER_WIDTH * 2,   /* Enable + Status register */
+         ACPI_FADT_REQUIRED},
 
-        {"Pm1bEventBlock", ACPI_FADT_OFFSET(xpm1b_event_block),
+        {"Pm1bEventBlock",
+         ACPI_FADT_OFFSET(xpm1b_event_block),
          ACPI_FADT_OFFSET(pm1b_event_block),
-         ACPI_FADT_OFFSET(pm1_event_length), 0},
+         ACPI_FADT_OFFSET(pm1_event_length),
+         ACPI_PM1_REGISTER_WIDTH * 2,   /* Enable + Status register */
+         0},
 
-        {"Pm1aControlBlock", ACPI_FADT_OFFSET(xpm1a_control_block),
+        {"Pm1aControlBlock",
+         ACPI_FADT_OFFSET(xpm1a_control_block),
          ACPI_FADT_OFFSET(pm1a_control_block),
-         ACPI_FADT_OFFSET(pm1_control_length), ACPI_FADT_REQUIRED},
+         ACPI_FADT_OFFSET(pm1_control_length),
+         ACPI_PM1_REGISTER_WIDTH,
+         ACPI_FADT_REQUIRED},
 
-        {"Pm1bControlBlock", ACPI_FADT_OFFSET(xpm1b_control_block),
+        {"Pm1bControlBlock",
+         ACPI_FADT_OFFSET(xpm1b_control_block),
          ACPI_FADT_OFFSET(pm1b_control_block),
-         ACPI_FADT_OFFSET(pm1_control_length), 0},
+         ACPI_FADT_OFFSET(pm1_control_length),
+         ACPI_PM1_REGISTER_WIDTH,
+         0},
 
-        {"Pm2ControlBlock", ACPI_FADT_OFFSET(xpm2_control_block),
+        {"Pm2ControlBlock",
+         ACPI_FADT_OFFSET(xpm2_control_block),
          ACPI_FADT_OFFSET(pm2_control_block),
-         ACPI_FADT_OFFSET(pm2_control_length), ACPI_FADT_SEPARATE_LENGTH},
+         ACPI_FADT_OFFSET(pm2_control_length),
+         ACPI_PM2_REGISTER_WIDTH,
+         ACPI_FADT_SEPARATE_LENGTH},
 
-        {"PmTimerBlock", ACPI_FADT_OFFSET(xpm_timer_block),
+        {"PmTimerBlock",
+         ACPI_FADT_OFFSET(xpm_timer_block),
          ACPI_FADT_OFFSET(pm_timer_block),
-         ACPI_FADT_OFFSET(pm_timer_length), ACPI_FADT_REQUIRED},
+         ACPI_FADT_OFFSET(pm_timer_length),
+         ACPI_PM_TIMER_WIDTH,
+         ACPI_FADT_REQUIRED},
 
-        {"Gpe0Block", ACPI_FADT_OFFSET(xgpe0_block),
+        {"Gpe0Block",
+         ACPI_FADT_OFFSET(xgpe0_block),
          ACPI_FADT_OFFSET(gpe0_block),
-         ACPI_FADT_OFFSET(gpe0_block_length), ACPI_FADT_SEPARATE_LENGTH},
+         ACPI_FADT_OFFSET(gpe0_block_length),
+         0,
+         ACPI_FADT_SEPARATE_LENGTH},
 
-        {"Gpe1Block", ACPI_FADT_OFFSET(xgpe1_block),
+        {"Gpe1Block",
+         ACPI_FADT_OFFSET(xgpe1_block),
          ACPI_FADT_OFFSET(gpe1_block),
-         ACPI_FADT_OFFSET(gpe1_block_length), ACPI_FADT_SEPARATE_LENGTH}
+         ACPI_FADT_OFFSET(gpe1_block_length),
+         0,
+         ACPI_FADT_SEPARATE_LENGTH}
 };
 
 #define ACPI_FADT_INFO_ENTRIES        (sizeof (fadt_info_table) / sizeof (struct acpi_fadt_info))
@@ -279,8 +304,9 @@ void acpi_tb_create_local_fadt(struct acpi_table_header *table, u32 length)
 
 static void acpi_tb_convert_fadt(void)
 {
-        u8 pm1_register_length;
-        struct acpi_generic_address *target;
+        u8 pm1_register_bit_width;
+        u8 pm1_register_byte_width;
+        struct acpi_generic_address *target64;
         u32 i;
 
         /* Update the local FADT table header length */
@@ -326,21 +352,22 @@ static void acpi_tb_convert_fadt(void)
         }
 
         /*
-         * Expand the ACPI 1.0 32-bit V1.0 addresses to the ACPI 2.0 64-bit "X"
-         * generic address structures as necessary.
+         * Expand the ACPI 1.0 32-bit addresses to the ACPI 2.0 64-bit "X"
+         * generic address structures as necessary. Later code will always use
+         * the 64-bit address structures.
          */
         for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {
-                target =
+                target64 =
                     ACPI_ADD_PTR(struct acpi_generic_address, &acpi_gbl_FADT,
-                                 fadt_info_table[i].target);
+                                 fadt_info_table[i].address64);
 
-                /* Expand only if the X target is null */
+                /* Expand only if the 64-bit X target is null */
 
-                if (!target->address) {
+                if (!target64->address) {
 
-                        /* The space_id is always I/O for the legacy address fields */
+                        /* The space_id is always I/O for the 32-bit legacy address fields */
 
-                        acpi_tb_init_generic_address(target,
+                        acpi_tb_init_generic_address(target64,
                                                      ACPI_ADR_SPACE_SYSTEM_IO,
                                                      *ACPI_ADD_PTR(u8,
                                                                    &acpi_gbl_FADT,
@@ -350,7 +377,7 @@ static void acpi_tb_convert_fadt(void)
                                                                           &acpi_gbl_FADT,
                                                                           fadt_info_table
                                                                           [i].
-                                                                          source));
+                                                                          address32));
                 }
         }
 
@@ -359,19 +386,53 @@ static void acpi_tb_convert_fadt(void)
         acpi_tb_validate_fadt();
 
         /*
-         * Get the length of the individual PM1 registers. Each register is
-         * defined to be the event block length / 2.
+         * Optionally check all register lengths against the default values and
+         * update them if they are incorrect.
          */
-        pm1_register_length = (u8)ACPI_DIV_2(acpi_gbl_FADT.pm1_event_length);
+        if (acpi_gbl_use_default_register_widths) {
+                for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {
+                        target64 =
+                            ACPI_ADD_PTR(struct acpi_generic_address,
+                                         &acpi_gbl_FADT,
+                                         fadt_info_table[i].address64);
+
+                        /*
+                         * If a valid register (Address != 0) and the (default_length > 0)
+                         * (Not a GPE register), then check the width against the default.
+                         */
+                        if ((target64->address) &&
+                            (fadt_info_table[i].default_length > 0) &&
+                            (fadt_info_table[i].default_length !=
+                             target64->bit_width)) {
+                                ACPI_WARNING((AE_INFO,
+                                              "Invalid length for %s: %d, using default %d",
+                                              fadt_info_table[i].name,
+                                              target64->bit_width,
+                                              fadt_info_table[i].
+                                              default_length));
+
+                                /* Incorrect size, set width to the default */
+
+                                target64->bit_width =
+                                    fadt_info_table[i].default_length;
+                        }
+                }
+        }
+
+        /*
+         * Get the length of the individual PM1 registers (enable and status).
+         * Each register is defined to be (event block length / 2).
+         */
+        pm1_register_bit_width =
+            (u8)ACPI_DIV_2(acpi_gbl_FADT.xpm1a_event_block.bit_width);
+        pm1_register_byte_width = (u8)ACPI_DIV_8(pm1_register_bit_width);
 
         /*
          * Adjust the lengths of the PM1 Event Blocks so that they can be used to
-         * access the PM1 status register(s).
+         * access the PM1 status register(s). Use (width / 2)
          */
-        acpi_gbl_FADT.xpm1a_event_block.bit_width =
-            (u8)ACPI_MUL_8(pm1_register_length);
-        acpi_gbl_FADT.xpm1b_event_block.bit_width =
-            (u8)ACPI_MUL_8(pm1_register_length);
+        acpi_gbl_FADT.xpm1a_event_block.bit_width = pm1_register_bit_width;
+        acpi_gbl_FADT.xpm1b_event_block.bit_width = pm1_register_bit_width;
 
         /*
          * Calculate separate GAS structs for the PM1 Enable registers.
@@ -398,9 +459,9 @@ static void acpi_tb_convert_fadt(void)
 
         acpi_tb_init_generic_address(&acpi_gbl_xpm1a_enable,
                                      acpi_gbl_FADT.xpm1a_event_block.space_id,
-                                     pm1_register_length,
+                                     pm1_register_byte_width,
                                      (acpi_gbl_FADT.xpm1a_event_block.address +
-                                      pm1_register_length));
+                                      pm1_register_byte_width));
         /* Don't forget to copy space_id of the GAS */
         acpi_gbl_xpm1a_enable.space_id =
             acpi_gbl_FADT.xpm1a_event_block.space_id;
@@ -417,38 +478,14 @@ static void acpi_tb_convert_fadt(void)
                                acpi_gbl_FADT.pm1_event_length);
                 acpi_tb_init_generic_address(&acpi_gbl_xpm1b_enable,
                                              acpi_gbl_FADT.xpm1b_event_block.space_id,
-                                             pm1_register_length,
+                                             pm1_register_byte_width,
                                              (acpi_gbl_FADT.xpm1b_event_block.
-                                              address + pm1_register_length));
+                                              address + pm1_register_byte_width));
                 /* Don't forget to copy space_id of the GAS */
                 acpi_gbl_xpm1b_enable.space_id =
                     acpi_gbl_FADT.xpm1b_event_block.space_id;
 
         }
-
-        if (acpi_gbl_use_default_register_widths) {
-                /*
-                 * Optionally, use the default sizes for the ACPI registers.
-                 * Some FADTs do not have the correct length(s).
-                 *
-                 * Note: Xpm1a_event_block and Xpm1b_event_block are used to access the PM1
-                 * status registers. The PM1 enable registers are created above.
-                 */
-                acpi_gbl_xpm1a_enable.bit_width = ACPI_PM1_REGISTER_WIDTH;
-                acpi_gbl_xpm1b_enable.bit_width = ACPI_PM1_REGISTER_WIDTH;
-
-                acpi_gbl_FADT.xpm1a_event_block.bit_width =
-                    ACPI_PM1_REGISTER_WIDTH;
-                acpi_gbl_FADT.xpm1b_event_block.bit_width =
-                    ACPI_PM1_REGISTER_WIDTH;
-                acpi_gbl_FADT.xpm1a_control_block.bit_width =
-                    ACPI_PM1_REGISTER_WIDTH;
-                acpi_gbl_FADT.xpm1b_control_block.bit_width =
-                    ACPI_PM1_REGISTER_WIDTH;
-                acpi_gbl_FADT.xpm2_control_block.bit_width =
-                    ACPI_PM2_REGISTER_WIDTH;
-                acpi_gbl_FADT.xpm_timer_block.bit_width = ACPI_PM_TIMER_WIDTH;
-        }
 }
 
 /******************************************************************************
@@ -511,10 +548,10 @@ static void acpi_tb_validate_fadt(void)
                  */
                 address64 = ACPI_ADD_PTR(struct acpi_generic_address,
                                          &acpi_gbl_FADT,
-                                         fadt_info_table[i].target);
+                                         fadt_info_table[i].address64);
                 address32 =
                     ACPI_ADD_PTR(u32, &acpi_gbl_FADT,
-                                 fadt_info_table[i].source);
+                                 fadt_info_table[i].address32);
                 length =
                     *ACPI_ADD_PTR(u8, &acpi_gbl_FADT,
                                   fadt_info_table[i].length);
@@ -522,7 +559,7 @@ static void acpi_tb_validate_fadt(void)
 
                 /*
                  * For each extended field, check for length mismatch between the
-                 * legacy length field and the corresonding 64-bit X length field.
+                 * legacy length field and the corresponding 64-bit X length field.
                  */
                 if (address64 && (address64->bit_width != ACPI_MUL_8(length))) {
                         ACPI_WARNING((AE_INFO,