struct acpi_generic_address *register_a,
struct acpi_generic_address *register_b);
+/******************************************************************************
+ *
+ * FUNCTION: acpi_hw_validate_register
+ *
+ * PARAMETERS: Reg - GAS register structure
+ * max_bit_width - Max bit_width supported (32 or 64)
+ * Address - Pointer to where the gas->address
+ * is returned
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Validate the contents of a GAS register. Checks the GAS
+ * pointer, Address, space_id, bit_width, and bit_offset.
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_hw_validate_register(struct acpi_generic_address *reg,
+ u8 max_bit_width, u64 *address)
+{
+
+ /* Must have a valid pointer to a GAS structure */
+
+ if (!reg) {
+ return (AE_BAD_PARAMETER);
+ }
+
+ /*
+ * Copy the target address. This handles possible alignment issues.
+ * Address must not be null. A null address also indicates an optional
+ * ACPI register that is not supported, so no error message.
+ */
+ ACPI_MOVE_64_TO_64(address, ®->address);
+ if (!(*address)) {
+ return (AE_BAD_ADDRESS);
+ }
+
+ /* Validate the space_iD */
+
+ if ((reg->space_id != ACPI_ADR_SPACE_SYSTEM_MEMORY) &&
+ (reg->space_id != ACPI_ADR_SPACE_SYSTEM_IO)) {
+ ACPI_ERROR((AE_INFO,
+ "Unsupported address space: 0x%X", reg->space_id));
+ return (AE_SUPPORT);
+ }
+
+ /* Validate the bit_width */
+
+ if ((reg->bit_width != 8) &&
+ (reg->bit_width != 16) &&
+ (reg->bit_width != 32) && (reg->bit_width != max_bit_width)) {
+ ACPI_ERROR((AE_INFO,
+ "Unsupported register bit width: 0x%X",
+ reg->bit_width));
+ return (AE_SUPPORT);
+ }
+
+ /* Validate the bit_offset. Just a warning for now. */
+
+ if (reg->bit_offset != 0) {
+ ACPI_WARNING((AE_INFO,
+ "Unsupported register bit offset: 0x%X",
+ reg->bit_offset));
+ }
+
+ return (AE_OK);
+}
+
+/******************************************************************************
+ *
+ * FUNCTION: acpi_hw_read
+ *
+ * PARAMETERS: Value - Where the value is returned
+ * Reg - GAS register structure
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Read from either memory or IO space. This is a 32-bit max
+ * version of acpi_read, used internally since the overhead of
+ * 64-bit values is not needed.
+ *
+ * LIMITATIONS: <These limitations also apply to acpi_hw_write>
+ * bit_width must be exactly 8, 16, or 32.
+ * space_iD must be system_memory or system_iO.
+ * bit_offset and access_width are currently ignored, as there has
+ * not been a need to implement these.
+ *
+ ******************************************************************************/
+
+acpi_status acpi_hw_read(u32 *value, struct acpi_generic_address *reg)
+{
+ u64 address;
+ acpi_status status;
+
+ ACPI_FUNCTION_NAME(hw_read);
+
+ /* Validate contents of the GAS register */
+
+ status = acpi_hw_validate_register(reg, 32, &address);
+ if (ACPI_FAILURE(status)) {
+ return (status);
+ }
+
+ /* Initialize entire 32-bit return value to zero */
+
+ *value = 0;
+
+ /*
+ * Two address spaces supported: Memory or IO. PCI_Config is
+ * not supported here because the GAS structure is insufficient
+ */
+ if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) {
+ status = acpi_os_read_memory((acpi_physical_address)
+ address, value, reg->bit_width);
+ } else { /* ACPI_ADR_SPACE_SYSTEM_IO, validated earlier */
+
+ status = acpi_hw_read_port((acpi_io_address)
+ address, value, reg->bit_width);
+ }
+
+ ACPI_DEBUG_PRINT((ACPI_DB_IO,
+ "Read: %8.8X width %2d from %8.8X%8.8X (%s)\n",
+ *value, reg->bit_width, ACPI_FORMAT_UINT64(address),
+ acpi_ut_get_region_name(reg->space_id)));
+
+ return (status);
+}
+
+/******************************************************************************
+ *
+ * FUNCTION: acpi_hw_write
+ *
+ * PARAMETERS: Value - Value to be written
+ * Reg - GAS register structure
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Write to either memory or IO space. This is a 32-bit max
+ * version of acpi_write, used internally since the overhead of
+ * 64-bit values is not needed.
+ *
+ ******************************************************************************/
+
+acpi_status acpi_hw_write(u32 value, struct acpi_generic_address *reg)
+{
+ u64 address;
+ acpi_status status;
+
+ ACPI_FUNCTION_NAME(hw_write);
+
+ /* Validate contents of the GAS register */
+
+ status = acpi_hw_validate_register(reg, 32, &address);
+ if (ACPI_FAILURE(status)) {
+ return (status);
+ }
+
+ /*
+ * Two address spaces supported: Memory or IO. PCI_Config is
+ * not supported here because the GAS structure is insufficient
+ */
+ if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) {
+ status = acpi_os_write_memory((acpi_physical_address)
+ address, value, reg->bit_width);
+ } else { /* ACPI_ADR_SPACE_SYSTEM_IO, validated earlier */
+
+ status = acpi_hw_write_port((acpi_io_address)
+ address, value, reg->bit_width);
+ }
+
+ ACPI_DEBUG_PRINT((ACPI_DB_IO,
+ "Wrote: %8.8X width %2d to %8.8X%8.8X (%s)\n",
+ value, reg->bit_width, ACPI_FORMAT_UINT64(address),
+ acpi_ut_get_region_name(reg->space_id)));
+
+ return (status);
+}
+
/*******************************************************************************
*
* FUNCTION: acpi_hw_clear_acpi_status
ACPI_FUNCTION_TRACE(hw_clear_acpi_status);
- ACPI_DEBUG_PRINT((ACPI_DB_IO, "About to write %04X to %0llX\n",
+ ACPI_DEBUG_PRINT((ACPI_DB_IO, "About to write %04X to %8.8X%8.8X\n",
ACPI_BITMASK_ALL_FIXED_STATUS,
- acpi_gbl_xpm1a_status.address));
+ ACPI_FORMAT_UINT64(acpi_gbl_xpm1a_status.address)));
lock_flags = acpi_os_acquire_lock(acpi_gbl_hardware_lock);
/******************************************************************************
*
+ * FUNCTION: acpi_hw_write_pm1_control
+ *
+ * PARAMETERS: pm1a_control - Value to be written to PM1A control
+ * pm1b_control - Value to be written to PM1B control
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Write the PM1 A/B control registers. These registers are
+ * different than than the PM1 A/B status and enable registers
+ * in that different values can be written to the A/B registers.
+ * Most notably, the SLP_TYP bits can be different, as per the
+ * values returned from the _Sx predefined methods.
+ *
+ ******************************************************************************/
+
+acpi_status acpi_hw_write_pm1_control(u32 pm1a_control, u32 pm1b_control)
+{
+ acpi_status status;
+
+ ACPI_FUNCTION_TRACE(hw_write_pm1_control);
+
+ status =
+ acpi_hw_write(pm1a_control, &acpi_gbl_FADT.xpm1a_control_block);
+ if (ACPI_FAILURE(status)) {
+ return_ACPI_STATUS(status);
+ }
+
+ if (acpi_gbl_FADT.xpm1b_control_block.address) {
+ status =
+ acpi_hw_write(pm1b_control,
+ &acpi_gbl_FADT.xpm1b_control_block);
+ }
+ return_ACPI_STATUS(status);
+}
+
+/******************************************************************************
+ *
* FUNCTION: acpi_hw_register_read
*
* PARAMETERS: register_id - ACPI Register ID
xpm1a_control_block,
&acpi_gbl_FADT.
xpm1b_control_block);
+
+ /*
+ * Zero the write-only bits. From the ACPI specification, "Hardware
+ * Write-Only Bits": "Upon reads to registers with write-only bits,
+ * software masks out all write-only bits."
+ */
+ value &= ~ACPI_PM1_CONTROL_WRITEONLY_BITS;
break;
case ACPI_REGISTER_PM2_CONTROL: /* 8-bit access */
- status = acpi_read(&value, &acpi_gbl_FADT.xpm2_control_block);
+ status =
+ acpi_hw_read(&value, &acpi_gbl_FADT.xpm2_control_block);
break;
case ACPI_REGISTER_PM_TIMER: /* 32-bit access */
- status = acpi_read(&value, &acpi_gbl_FADT.xpm_timer_block);
+ status = acpi_hw_read(&value, &acpi_gbl_FADT.xpm_timer_block);
break;
case ACPI_REGISTER_SMI_COMMAND_BLOCK: /* 8-bit access */
status =
- acpi_os_read_port(acpi_gbl_FADT.smi_command, &value, 8);
+ acpi_hw_read_port(acpi_gbl_FADT.smi_command, &value, 8);
break;
default:
switch (register_id) {
case ACPI_REGISTER_PM1_STATUS: /* PM1 A/B: 16-bit access each */
-
- /* Perform a read first to preserve certain bits (per ACPI spec) */
-
- status = acpi_hw_read_multiple(&read_value,
- &acpi_gbl_xpm1a_status,
- &acpi_gbl_xpm1b_status);
- if (ACPI_FAILURE(status)) {
- goto exit;
- }
-
- /* Insert the bits to be preserved */
-
- ACPI_INSERT_BITS(value, ACPI_PM1_STATUS_PRESERVED_BITS,
- read_value);
-
- /* Now we can write the data */
+ /*
+ * Handle the "ignored" bit in PM1 Status. According to the ACPI
+ * specification, ignored bits are to be preserved when writing.
+ * Normally, this would mean a read/modify/write sequence. However,
+ * preserving a bit in the status register is different. Writing a
+ * one clears the status, and writing a zero preserves the status.
+ * Therefore, we must always write zero to the ignored bit.
+ *
+ * This behavior is clarified in the ACPI 4.0 specification.
+ */
+ value &= ~ACPI_PM1_STATUS_PRESERVED_BITS;
status = acpi_hw_write_multiple(value,
&acpi_gbl_xpm1a_status,
xpm1b_control_block);
break;
- case ACPI_REGISTER_PM1A_CONTROL: /* 16-bit access */
-
- status = acpi_write(value, &acpi_gbl_FADT.xpm1a_control_block);
- break;
+ case ACPI_REGISTER_PM2_CONTROL: /* 8-bit access */
- case ACPI_REGISTER_PM1B_CONTROL: /* 16-bit access */
+ /*
+ * For control registers, all reserved bits must be preserved,
+ * as per the ACPI spec.
+ */
+ status =
+ acpi_hw_read(&read_value,
+ &acpi_gbl_FADT.xpm2_control_block);
+ if (ACPI_FAILURE(status)) {
+ goto exit;
+ }
- status = acpi_write(value, &acpi_gbl_FADT.xpm1b_control_block);
- break;
+ /* Insert the bits to be preserved */
- case ACPI_REGISTER_PM2_CONTROL: /* 8-bit access */
+ ACPI_INSERT_BITS(value, ACPI_PM2_CONTROL_PRESERVED_BITS,
+ read_value);
- status = acpi_write(value, &acpi_gbl_FADT.xpm2_control_block);
+ status =
+ acpi_hw_write(value, &acpi_gbl_FADT.xpm2_control_block);
break;
case ACPI_REGISTER_PM_TIMER: /* 32-bit access */
- status = acpi_write(value, &acpi_gbl_FADT.xpm_timer_block);
+ status = acpi_hw_write(value, &acpi_gbl_FADT.xpm_timer_block);
break;
case ACPI_REGISTER_SMI_COMMAND_BLOCK: /* 8-bit access */
/* SMI_CMD is currently always in IO space */
status =
- acpi_os_write_port(acpi_gbl_FADT.smi_command, value, 8);
+ acpi_hw_write_port(acpi_gbl_FADT.smi_command, value, 8);
break;
default:
/* The first register is always required */
- status = acpi_read(&value_a, register_a);
+ status = acpi_hw_read(&value_a, register_a);
if (ACPI_FAILURE(status)) {
return (status);
}
/* Second register is optional */
if (register_b->address) {
- status = acpi_read(&value_b, register_b);
+ status = acpi_hw_read(&value_b, register_b);
if (ACPI_FAILURE(status)) {
return (status);
}
}
- /* Shift the B bits above the A bits */
-
- *value = value_a | (value_b << register_a->bit_width);
+ /*
+ * OR the two return values together. No shifting or masking is necessary,
+ * because of how the PM1 registers are defined in the ACPI specification:
+ *
+ * "Although the bits can be split between the two register blocks (each
+ * register block has a unique pointer within the FADT), the bit positions
+ * are maintained. The register block with unimplemented bits (that is,
+ * those implemented in the other register block) always returns zeros,
+ * and writes have no side effects"
+ */
+ *value = (value_a | value_b);
return (AE_OK);
}
/* The first register is always required */
- status = acpi_write(value, register_a);
+ status = acpi_hw_write(value, register_a);
if (ACPI_FAILURE(status)) {
return (status);
}
- /* Second register is optional */
-
+ /*
+ * Second register is optional
+ *
+ * No bit shifting or clearing is necessary, because of how the PM1
+ * registers are defined in the ACPI specification:
+ *
+ * "Although the bits can be split between the two register blocks (each
+ * register block has a unique pointer within the FADT), the bit positions
+ * are maintained. The register block with unimplemented bits (that is,
+ * those implemented in the other register block) always returns zeros,
+ * and writes have no side effects"
+ */
if (register_b->address) {
-
- /* Normalize the B bits before write */
-
- status = acpi_write(value >> register_a->bit_width, register_b);
+ status = acpi_hw_write(value, register_b);
}
return (status);
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff