u-boot/drivers/sysreset/sysreset_x86.c
Bin Meng ef329a6a73 sysreset: Remove DM_FLAG_PRE_RELOC flag in various drivers
When a driver declares DM_FLAG_PRE_RELOC flag, it wishes to be
bound before relocation. However due to a bug in the DM core,
the flag only takes effect when devices are statically declared
via U_BOOT_DEVICE(). This bug has been fixed recently by commit
"dm: core: Respect drivers with the DM_FLAG_PRE_RELOC flag in
lists_bind_fdt()", but with the fix, it has a side effect that
all existing drivers that declared DM_FLAG_PRE_RELOC flag will
be bound before relocation now. This may expose potential boot
failure on some boards due to insufficient memory during the
pre-relocation stage.

To mitigate this potential impact, the following changes are
implemented:

- Remove DM_FLAG_PRE_RELOC flag in the driver, if the driver
  only supports configuration from device tree (OF_CONTROL)
- Keep DM_FLAG_PRE_RELOC flag in the driver only if the device
  is statically declared via U_BOOT_DEVICE()
- Surround DM_FLAG_PRE_RELOC flag with OF_CONTROL check, for
  drivers that support both statically declared devices and
  configuration from device tree

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
2018-11-14 09:16:28 -08:00

48 lines
895 B
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2018, Bin Meng <bmeng.cn@gmail.com>
*
* Generic reset driver for x86 processor
*/
#include <common.h>
#include <dm.h>
#include <sysreset.h>
#include <asm/io.h>
#include <asm/processor.h>
static int x86_sysreset_request(struct udevice *dev, enum sysreset_t type)
{
int value;
switch (type) {
case SYSRESET_WARM:
value = SYS_RST | RST_CPU;
break;
case SYSRESET_COLD:
value = SYS_RST | RST_CPU | FULL_RST;
break;
default:
return -ENOSYS;
}
outb(value, IO_PORT_RESET);
return -EINPROGRESS;
}
static const struct udevice_id x86_sysreset_ids[] = {
{ .compatible = "x86,reset" },
{ }
};
static struct sysreset_ops x86_sysreset_ops = {
.request = x86_sysreset_request,
};
U_BOOT_DRIVER(x86_sysreset) = {
.name = "x86-sysreset",
.id = UCLASS_SYSRESET,
.of_match = x86_sysreset_ids,
.ops = &x86_sysreset_ops,
};