u-boot-brain/drivers/timer/dw-apb-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

90 lines
1.8 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Designware APB Timer driver
*
* Copyright (C) 2018 Marek Vasut <marex@denx.de>
*/
#include <common.h>
#include <dm.h>
#include <clk.h>
#include <timer.h>
#include <asm/io.h>
#include <asm/arch/timer.h>
#define DW_APB_LOAD_VAL 0x0
#define DW_APB_CURR_VAL 0x4
#define DW_APB_CTRL 0x8
DECLARE_GLOBAL_DATA_PTR;
struct dw_apb_timer_priv {
fdt_addr_t regs;
};
static int dw_apb_timer_get_count(struct udevice *dev, u64 *count)
{
struct dw_apb_timer_priv *priv = dev_get_priv(dev);
/*
* The DW APB counter counts down, but this function
* requires the count to be incrementing. Invert the
* result.
*/
*count = ~readl(priv->regs + DW_APB_CURR_VAL);
return 0;
}
static int dw_apb_timer_probe(struct udevice *dev)
{
struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev);
struct dw_apb_timer_priv *priv = dev_get_priv(dev);
struct clk clk;
int ret;
ret = clk_get_by_index(dev, 0, &clk);
if (ret)
return ret;
uc_priv->clock_rate = clk_get_rate(&clk);
clk_free(&clk);
/* init timer */
writel(0xffffffff, priv->regs + DW_APB_LOAD_VAL);
writel(0xffffffff, priv->regs + DW_APB_CURR_VAL);
setbits_le32(priv->regs + DW_APB_CTRL, 0x3);
return 0;
}
static int dw_apb_timer_ofdata_to_platdata(struct udevice *dev)
{
struct dw_apb_timer_priv *priv = dev_get_priv(dev);
priv->regs = dev_read_addr(dev);
return 0;
}
static const struct timer_ops dw_apb_timer_ops = {
.get_count = dw_apb_timer_get_count,
};
static const struct udevice_id dw_apb_timer_ids[] = {
{ .compatible = "snps,dw-apb-timer" },
{}
};
U_BOOT_DRIVER(dw_apb_timer) = {
.name = "dw_apb_timer",
.id = UCLASS_TIMER,
.ops = &dw_apb_timer_ops,
.probe = dw_apb_timer_probe,
.of_match = dw_apb_timer_ids,
.ofdata_to_platdata = dw_apb_timer_ofdata_to_platdata,
.priv_auto_alloc_size = sizeof(struct dw_apb_timer_priv),
};