u-boot/drivers/misc/rockchip-efuse.c
Simon Glass 8729b1ae2c misc: Update read() and write() methods to return bytes xfered
At present these functions return 0 on success. For some devices we want
to know how many bytes were transferred. It seems useful to adjust the API
to be more like the POSIX read() and write() functions.

Update these two methods, a test and all users.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Patrick Delaunay <patrick.delaunay@st.com>
2018-11-20 19:14:22 -07:00

160 lines
4 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* eFuse driver for Rockchip devices
*
* Copyright 2017, Theobroma Systems Design und Consulting GmbH
* Written by Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
*/
#include <common.h>
#include <asm/io.h>
#include <command.h>
#include <display_options.h>
#include <dm.h>
#include <linux/bitops.h>
#include <linux/delay.h>
#include <misc.h>
#define RK3399_A_SHIFT 16
#define RK3399_A_MASK 0x3ff
#define RK3399_NFUSES 32
#define RK3399_BYTES_PER_FUSE 4
#define RK3399_STROBSFTSEL BIT(9)
#define RK3399_RSB BIT(7)
#define RK3399_PD BIT(5)
#define RK3399_PGENB BIT(3)
#define RK3399_LOAD BIT(2)
#define RK3399_STROBE BIT(1)
#define RK3399_CSB BIT(0)
struct rockchip_efuse_regs {
u32 ctrl; /* 0x00 efuse control register */
u32 dout; /* 0x04 efuse data out register */
u32 rf; /* 0x08 efuse redundancy bit used register */
u32 _rsvd0;
u32 jtag_pass; /* 0x10 JTAG password */
u32 strobe_finish_ctrl;
/* 0x14 efuse strobe finish control register */
};
struct rockchip_efuse_platdata {
void __iomem *base;
struct clk *clk;
};
#if defined(DEBUG)
static int dump_efuses(cmd_tbl_t *cmdtp, int flag,
int argc, char * const argv[])
{
/*
* N.B.: This function is tailored towards the RK3399 and assumes that
* there's always 32 fuses x 32 bits (i.e. 128 bytes of data) to
* be read.
*/
struct udevice *dev;
u8 fuses[128];
int ret;
/* retrieve the device */
ret = uclass_get_device_by_driver(UCLASS_MISC,
DM_GET_DRIVER(rockchip_efuse), &dev);
if (ret) {
printf("%s: no misc-device found\n", __func__);
return 0;
}
ret = misc_read(dev, 0, &fuses, sizeof(fuses));
if (ret < 0) {
printf("%s: misc_read failed\n", __func__);
return 0;
}
printf("efuse-contents:\n");
print_buffer(0, fuses, 1, 128, 16);
return 0;
}
U_BOOT_CMD(
rk3399_dump_efuses, 1, 1, dump_efuses,
"Dump the content of the efuses",
""
);
#endif
static int rockchip_rk3399_efuse_read(struct udevice *dev, int offset,
void *buf, int size)
{
struct rockchip_efuse_platdata *plat = dev_get_platdata(dev);
struct rockchip_efuse_regs *efuse =
(struct rockchip_efuse_regs *)plat->base;
unsigned int addr_start, addr_end, addr_offset;
u32 out_value;
u8 bytes[RK3399_NFUSES * RK3399_BYTES_PER_FUSE];
int i = 0;
u32 addr;
addr_start = offset / RK3399_BYTES_PER_FUSE;
addr_offset = offset % RK3399_BYTES_PER_FUSE;
addr_end = DIV_ROUND_UP(offset + size, RK3399_BYTES_PER_FUSE);
/* cap to the size of the efuse block */
if (addr_end > RK3399_NFUSES)
addr_end = RK3399_NFUSES;
writel(RK3399_LOAD | RK3399_PGENB | RK3399_STROBSFTSEL | RK3399_RSB,
&efuse->ctrl);
udelay(1);
for (addr = addr_start; addr < addr_end; addr++) {
setbits_le32(&efuse->ctrl,
RK3399_STROBE | (addr << RK3399_A_SHIFT));
udelay(1);
out_value = readl(&efuse->dout);
clrbits_le32(&efuse->ctrl, RK3399_STROBE);
udelay(1);
memcpy(&bytes[i], &out_value, RK3399_BYTES_PER_FUSE);
i += RK3399_BYTES_PER_FUSE;
}
/* Switch to standby mode */
writel(RK3399_PD | RK3399_CSB, &efuse->ctrl);
memcpy(buf, bytes + addr_offset, size);
return 0;
}
static int rockchip_efuse_read(struct udevice *dev, int offset,
void *buf, int size)
{
return rockchip_rk3399_efuse_read(dev, offset, buf, size);
}
static const struct misc_ops rockchip_efuse_ops = {
.read = rockchip_efuse_read,
};
static int rockchip_efuse_ofdata_to_platdata(struct udevice *dev)
{
struct rockchip_efuse_platdata *plat = dev_get_platdata(dev);
plat->base = dev_read_addr_ptr(dev);
return 0;
}
static const struct udevice_id rockchip_efuse_ids[] = {
{ .compatible = "rockchip,rk3399-efuse" },
{}
};
U_BOOT_DRIVER(rockchip_efuse) = {
.name = "rockchip_efuse",
.id = UCLASS_MISC,
.of_match = rockchip_efuse_ids,
.ofdata_to_platdata = rockchip_efuse_ofdata_to_platdata,
.platdata_auto_alloc_size = sizeof(struct rockchip_efuse_platdata),
.ops = &rockchip_efuse_ops,
};