drivers/platform/mips/rs780e-acpi.c

Source file repositories/reference/linux-study-clean/drivers/platform/mips/rs780e-acpi.c

File Facts

System
Linux kernel
Corpus path
drivers/platform/mips/rs780e-acpi.c
Extension
.c
Size
3940 bytes
Lines
166
Domain
Driver Families
Bucket
drivers/platform
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0
#include <linux/io.h>
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/export.h>
#include <linux/of.h>
#include <linux/platform_device.h>

static unsigned long acpi_iobase;

#define ACPI_PM_EVT_BLK         (acpi_iobase + 0x00) /* 4 bytes */
#define ACPI_PM_CNT_BLK         (acpi_iobase + 0x04) /* 2 bytes */
#define ACPI_PMA_CNT_BLK        (acpi_iobase + 0x0F) /* 1 byte */
#define ACPI_PM_TMR_BLK         (acpi_iobase + 0x18) /* 4 bytes */
#define ACPI_GPE0_BLK           (acpi_iobase + 0x10) /* 8 bytes */
#define ACPI_END                (acpi_iobase + 0x80)

#define PM_INDEX        0xCD6
#define PM_DATA         0xCD7
#define PM2_INDEX       0xCD0
#define PM2_DATA        0xCD1

static void pmio_write_index(u16 index, u8 reg, u8 value)
{
	outb(reg, index);
	outb(value, index + 1);
}

static u8 pmio_read_index(u16 index, u8 reg)
{
	outb(reg, index);
	return inb(index + 1);
}

static void pm_iowrite(u8 reg, u8 value)
{
	pmio_write_index(PM_INDEX, reg, value);
}

static u8 pm_ioread(u8 reg)
{
	return pmio_read_index(PM_INDEX, reg);
}

static void pm2_iowrite(u8 reg, u8 value)
{
	pmio_write_index(PM2_INDEX, reg, value);
}

static u8 pm2_ioread(u8 reg)
{
	return pmio_read_index(PM2_INDEX, reg);
}

static void acpi_hw_clear_status(void)
{
	u16 value;

	/* PMStatus: Clear WakeStatus/PwrBtnStatus */
	value = inw(ACPI_PM_EVT_BLK);
	value |= (1 << 8 | 1 << 15);
	outw(value, ACPI_PM_EVT_BLK);

	/* GPEStatus: Clear all generated events */
	outl(inl(ACPI_GPE0_BLK), ACPI_GPE0_BLK);
}

static void acpi_registers_setup(void)
{
	u32 value;

	/* PM Status Base */
	pm_iowrite(0x20, ACPI_PM_EVT_BLK & 0xff);
	pm_iowrite(0x21, ACPI_PM_EVT_BLK >> 8);

	/* PM Control Base */
	pm_iowrite(0x22, ACPI_PM_CNT_BLK & 0xff);
	pm_iowrite(0x23, ACPI_PM_CNT_BLK >> 8);

	/* GPM Base */
	pm_iowrite(0x28, ACPI_GPE0_BLK & 0xff);
	pm_iowrite(0x29, ACPI_GPE0_BLK >> 8);

	/* ACPI End */
	pm_iowrite(0x2e, ACPI_END & 0xff);
	pm_iowrite(0x2f, ACPI_END >> 8);

	/* IO Decode: When AcpiDecodeEnable set, South-Bridge uses the contents
	 * of the PM registers at index 0x20~0x2B to decode ACPI I/O address. */
	pm_iowrite(0x0e, 1 << 3);

Annotation

Implementation Notes