u-boot/drivers/pinctrl/pinctrl-single.c
Bin Meng ad0e804843 pinctrl: 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

141 lines
3.8 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) EETS GmbH, 2017, Felix Brack <f.brack@eets.ch>
*/
#include <common.h>
#include <dm.h>
#include <dm/pinctrl.h>
#include <linux/libfdt.h>
#include <asm/io.h>
DECLARE_GLOBAL_DATA_PTR;
struct single_pdata {
fdt_addr_t base; /* first configuration register */
int offset; /* index of last configuration register */
u32 mask; /* configuration-value mask bits */
int width; /* configuration register bit width */
};
struct single_fdt_pin_cfg {
fdt32_t reg; /* configuration register offset */
fdt32_t val; /* configuration register value */
};
/**
* single_configure_pins() - Configure pins based on FDT data
*
* @dev: Pointer to single pin configuration device which is the parent of
* the pins node holding the pin configuration data.
* @pins: Pointer to the first element of an array of register/value pairs
* of type 'struct single_fdt_pin_cfg'. Each such pair describes the
* the pin to be configured and the value to be used for configuration.
* This pointer points to a 'pinctrl-single,pins' property in the
* device-tree.
* @size: Size of the 'pins' array in bytes.
* The number of register/value pairs in the 'pins' array therefore
* equals to 'size / sizeof(struct single_fdt_pin_cfg)'.
*/
static int single_configure_pins(struct udevice *dev,
const struct single_fdt_pin_cfg *pins,
int size)
{
struct single_pdata *pdata = dev->platdata;
int count = size / sizeof(struct single_fdt_pin_cfg);
phys_addr_t n, reg;
u32 val;
for (n = 0; n < count; n++, pins++) {
reg = fdt32_to_cpu(pins->reg);
if ((reg < 0) || (reg > pdata->offset)) {
dev_dbg(dev, " invalid register offset 0x%pa\n", &reg);
continue;
}
reg += pdata->base;
val = fdt32_to_cpu(pins->val) & pdata->mask;
switch (pdata->width) {
case 16:
writew((readw(reg) & ~pdata->mask) | val, reg);
break;
case 32:
writel((readl(reg) & ~pdata->mask) | val, reg);
break;
default:
dev_warn(dev, "unsupported register width %i\n",
pdata->width);
continue;
}
dev_dbg(dev, " reg/val 0x%pa/0x%08x\n", &reg, val);
}
return 0;
}
static int single_set_state(struct udevice *dev,
struct udevice *config)
{
const void *fdt = gd->fdt_blob;
const struct single_fdt_pin_cfg *prop;
int len;
prop = fdt_getprop(fdt, dev_of_offset(config), "pinctrl-single,pins",
&len);
if (prop) {
dev_dbg(dev, "configuring pins for %s\n", config->name);
if (len % sizeof(struct single_fdt_pin_cfg)) {
dev_dbg(dev, " invalid pin configuration in fdt\n");
return -FDT_ERR_BADSTRUCTURE;
}
single_configure_pins(dev, prop, len);
len = 0;
}
return len;
}
static int single_ofdata_to_platdata(struct udevice *dev)
{
fdt_addr_t addr;
u32 of_reg[2];
int res;
struct single_pdata *pdata = dev->platdata;
pdata->width = fdtdec_get_int(gd->fdt_blob, dev_of_offset(dev),
"pinctrl-single,register-width", 0);
res = fdtdec_get_int_array(gd->fdt_blob, dev_of_offset(dev),
"reg", of_reg, 2);
if (res)
return res;
pdata->offset = of_reg[1] - pdata->width / 8;
addr = devfdt_get_addr(dev);
if (addr == FDT_ADDR_T_NONE) {
dev_dbg(dev, "no valid base register address\n");
return -EINVAL;
}
pdata->base = addr;
pdata->mask = fdtdec_get_int(gd->fdt_blob, dev_of_offset(dev),
"pinctrl-single,function-mask",
0xffffffff);
return 0;
}
const struct pinctrl_ops single_pinctrl_ops = {
.set_state = single_set_state,
};
static const struct udevice_id single_pinctrl_match[] = {
{ .compatible = "pinctrl-single" },
{ /* sentinel */ }
};
U_BOOT_DRIVER(single_pinctrl) = {
.name = "single-pinctrl",
.id = UCLASS_PINCTRL,
.of_match = single_pinctrl_match,
.ops = &single_pinctrl_ops,
.platdata_auto_alloc_size = sizeof(struct single_pdata),
.ofdata_to_platdata = single_ofdata_to_platdata,
};