u-boot/drivers/misc/qfw_pio.c
Asherah Connor 5b0b43e0e2 x86: qemu: move QFW to its own uclass
We move qfw into its own uclass and split the PIO functions into a
specific driver for that uclass.  The PIO driver is selected in the
qemu-x86 board config (this covers x86 and x86_64).

include/qfw.h is cleaned up and documentation added.

Signed-off-by: Asherah Connor <ashe@kivikakk.ee>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
2021-04-12 17:44:55 -04:00

69 lines
1.6 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* PIO interface for QFW
*
* (C) Copyright 2015 Miao Yan <yanmiaobest@gmail.com>
* (C) Copyright 2021 Asherah Connor <ashe@kivikakk.ee>
*/
#define LOG_CATEGORY UCLASS_QFW
#include <asm/io.h>
#include <dm/device.h>
#include <qfw.h>
/*
* PIO ports are correct for x86, which appears to be the only arch that uses
* PIO.
*/
#define FW_CONTROL_PORT 0x510
#define FW_DATA_PORT 0x511
#define FW_DMA_PORT_LOW 0x514
#define FW_DMA_PORT_HIGH 0x518
static void qfw_pio_read_entry_io(struct udevice *dev, u16 entry, u32 size,
void *address)
{
/*
* writing FW_CFG_INVALID will cause read operation to resume at last
* offset, otherwise read will start at offset 0
*
* Note: on platform where the control register is IO port, the
* endianness is little endian.
*/
if (entry != FW_CFG_INVALID)
outw(cpu_to_le16(entry), FW_CONTROL_PORT);
/* the endianness of data register is string-preserving */
u32 i = 0;
u8 *data = address;
while (size--)
data[i++] = inb(FW_DATA_PORT);
}
/* Read configuration item using fw_cfg DMA interface */
static void qfw_pio_read_entry_dma(struct udevice *dev, struct qfw_dma *dma)
{
/* the DMA address register is big-endian */
outl(cpu_to_be32((uintptr_t)dma), FW_DMA_PORT_HIGH);
while (be32_to_cpu(dma->control) & ~FW_CFG_DMA_ERROR);
}
static int qfw_pio_probe(struct udevice *dev)
{
return qfw_register(dev);
}
static struct dm_qfw_ops qfw_pio_ops = {
.read_entry_io = qfw_pio_read_entry_io,
.read_entry_dma = qfw_pio_read_entry_dma,
};
U_BOOT_DRIVER(qfw_pio) = {
.name = "qfw_pio",
.id = UCLASS_QFW,
.probe = qfw_pio_probe,
.ops = &qfw_pio_ops,
};