u-boot-brain/drivers/timer/sti-timer.c
Bin Meng d7a184d4a7 timer: 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

78 lines
1.7 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2017, STMicroelectronics - All Rights Reserved
* Author(s): Patrice Chotard, <patrice.chotard@st.com> for STMicroelectronics.
*/
#include <common.h>
#include <dm.h>
#include <fdtdec.h>
#include <timer.h>
#include <asm/io.h>
#include <asm/arch-armv7/globaltimer.h>
DECLARE_GLOBAL_DATA_PTR;
struct sti_timer_priv {
struct globaltimer *global_timer;
};
static int sti_timer_get_count(struct udevice *dev, u64 *count)
{
struct sti_timer_priv *priv = dev_get_priv(dev);
struct globaltimer *global_timer = priv->global_timer;
u32 low, high;
u64 timer;
u32 old = readl(&global_timer->cnt_h);
while (1) {
low = readl(&global_timer->cnt_l);
high = readl(&global_timer->cnt_h);
if (old == high)
break;
else
old = high;
}
timer = high;
*count = (u64)((timer << 32) | low);
return 0;
}
static int sti_timer_probe(struct udevice *dev)
{
struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
struct sti_timer_priv *priv = dev_get_priv(dev);
fdt_addr_t addr;
uc_priv->clock_rate = CONFIG_SYS_HZ_CLOCK;
/* get arm global timer base address */
addr = fdtdec_get_addr(gd->fdt_blob, dev_of_offset(dev), "reg");
priv->global_timer = (struct globaltimer *)addr;
/* init timer */
writel(0x01, &priv->global_timer->ctl);
return 0;
}
static const struct timer_ops sti_timer_ops = {
.get_count = sti_timer_get_count,
};
static const struct udevice_id sti_timer_ids[] = {
{ .compatible = "arm,cortex-a9-global-timer" },
{}
};
U_BOOT_DRIVER(sti_timer) = {
.name = "sti_timer",
.id = UCLASS_TIMER,
.of_match = sti_timer_ids,
.priv_auto_alloc_size = sizeof(struct sti_timer_priv),
.probe = sti_timer_probe,
.ops = &sti_timer_ops,
};