u-boot-brain/drivers/gpio/stm32f7_gpio.c
Bin Meng 695c4994ac gpio: 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>
Reviewed-by: Patrick Delaunay <patrick.delaunay@st.com>
2018-11-14 09:16:28 -08:00

129 lines
3.2 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2017, STMicroelectronics - All Rights Reserved
* Author(s): Vikas Manocha, <vikas.manocha@st.com> for STMicroelectronics.
*/
#include <common.h>
#include <clk.h>
#include <dm.h>
#include <fdtdec.h>
#include <asm/arch/gpio.h>
#include <asm/arch/stm32.h>
#include <asm/gpio.h>
#include <asm/io.h>
#include <linux/errno.h>
#include <linux/io.h>
#define STM32_GPIOS_PER_BANK 16
#define MODE_BITS(gpio_pin) (gpio_pin * 2)
#define MODE_BITS_MASK 3
#define BSRR_BIT(gpio_pin, value) BIT(gpio_pin + (value ? 0 : 16))
static int stm32_gpio_direction_input(struct udevice *dev, unsigned offset)
{
struct stm32_gpio_priv *priv = dev_get_priv(dev);
struct stm32_gpio_regs *regs = priv->regs;
int bits_index = MODE_BITS(offset);
int mask = MODE_BITS_MASK << bits_index;
clrsetbits_le32(&regs->moder, mask, STM32_GPIO_MODE_IN << bits_index);
return 0;
}
static int stm32_gpio_direction_output(struct udevice *dev, unsigned offset,
int value)
{
struct stm32_gpio_priv *priv = dev_get_priv(dev);
struct stm32_gpio_regs *regs = priv->regs;
int bits_index = MODE_BITS(offset);
int mask = MODE_BITS_MASK << bits_index;
clrsetbits_le32(&regs->moder, mask, STM32_GPIO_MODE_OUT << bits_index);
writel(BSRR_BIT(offset, value), &regs->bsrr);
return 0;
}
static int stm32_gpio_get_value(struct udevice *dev, unsigned offset)
{
struct stm32_gpio_priv *priv = dev_get_priv(dev);
struct stm32_gpio_regs *regs = priv->regs;
return readl(&regs->idr) & BIT(offset) ? 1 : 0;
}
static int stm32_gpio_set_value(struct udevice *dev, unsigned offset, int value)
{
struct stm32_gpio_priv *priv = dev_get_priv(dev);
struct stm32_gpio_regs *regs = priv->regs;
writel(BSRR_BIT(offset, value), &regs->bsrr);
return 0;
}
static const struct dm_gpio_ops gpio_stm32_ops = {
.direction_input = stm32_gpio_direction_input,
.direction_output = stm32_gpio_direction_output,
.get_value = stm32_gpio_get_value,
.set_value = stm32_gpio_set_value,
};
static int gpio_stm32_probe(struct udevice *dev)
{
struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
struct stm32_gpio_priv *priv = dev_get_priv(dev);
fdt_addr_t addr;
const char *name;
addr = dev_read_addr(dev);
if (addr == FDT_ADDR_T_NONE)
return -EINVAL;
priv->regs = (struct stm32_gpio_regs *)addr;
name = dev_read_string(dev, "st,bank-name");
if (!name)
return -EINVAL;
uc_priv->bank_name = name;
uc_priv->gpio_count = dev_read_u32_default(dev, "ngpios",
STM32_GPIOS_PER_BANK);
debug("%s, addr = 0x%p, bank_name = %s\n", __func__, (u32 *)priv->regs,
uc_priv->bank_name);
#ifdef CONFIG_CLK
struct clk clk;
int ret;
ret = clk_get_by_index(dev, 0, &clk);
if (ret < 0)
return ret;
ret = clk_enable(&clk);
if (ret) {
dev_err(dev, "failed to enable clock\n");
return ret;
}
debug("clock enabled for device %s\n", dev->name);
#endif
return 0;
}
static const struct udevice_id stm32_gpio_ids[] = {
{ .compatible = "st,stm32-gpio" },
{ }
};
U_BOOT_DRIVER(gpio_stm32) = {
.name = "gpio_stm32",
.id = UCLASS_GPIO,
.of_match = stm32_gpio_ids,
.probe = gpio_stm32_probe,
.ops = &gpio_stm32_ops,
.flags = DM_UC_FLAG_SEQ_ALIAS,
.priv_auto_alloc_size = sizeof(struct stm32_gpio_priv),
};