[U-Boot] [PATCH v2 2/5] rockchip: efuse: add (misc) driver for RK3399 non-secure efuse block
Simon Glass
sjg at chromium.org
Wed May 3 10:06:41 UTC 2017
Hi Philipp,
On 29 April 2017 at 21:48, Simon Glass <sjg at chromium.org> wrote:
>
> Hi Philipp,
>
> On 28 April 2017 at 09:11, Philipp Tomsich
> <philipp.tomsich at theobroma-systems.com> wrote:
> > This adds a simple driver for reading the efuse block of the RK3399.
> > It should be easy enough to add drivers for other devices (e.g. the
> > RK3328, RK3368, etc.) by passing the device details via driver_data.
> >
> > Unlike the kernel driver (using the nvmem subsystem), we don't expose
> > the efuse as multiple named cells, but rather as a linear memory that
> > can be read using misc_read(...).
> >
> > The primary use case (as of today) is the generation of a 'serial#'
> > (and a 'cpuid#') environment variable for the RK3399-Q7 (Puma)
> > system-on-module.
> >
> > Note that this adds a debug-only (i.e. only if DEBUG is defined)
> > command 'rk3399_dump_efuses' that dumps the efuse block's content.
> > N.B.: The name 'rk3399_dump_efuses' was intentionally chosen to
> > include a SoC-name (together with a comment in the function) to
> > remind whoever adds support for additional SoCs that this
> > function currently makes assumptions regarding the size of the
> > fuse-box based on the RK3399. The hope is that the function is
> > adjusted to reflect any changes resulting from generalising the
> > driver for multiple SoCs and is then renamed.
> >
> > Signed-off-by: Philipp Tomsich <philipp.tomsich at theobroma-systems.com>
> > Tested-by: Klaus Goger <klaus.goger at theobroma-systems.com>
> > ---
> >
> > Changes in v2: None
> >
> > drivers/misc/Kconfig | 14 ++++
> > drivers/misc/Makefile | 1 +
> > drivers/misc/rockchip-efuse.c | 163 ++++++++++++++++++++++++++++++++++++++++++
> > 3 files changed, 178 insertions(+)
> > create mode 100644 drivers/misc/rockchip-efuse.c
>
> Reviewed-by: Simon Glass <sjg at chromium.org>
>
> But please see below.
>
> >
> > diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
> > index 1aae4bc..ed57414 100644
> > --- a/drivers/misc/Kconfig
> > +++ b/drivers/misc/Kconfig
> > @@ -20,6 +20,19 @@ config ALTERA_SYSID
> > Select this to enable a sysid for Altera devices. Please find
> > details on the "Embedded Peripherals IP User Guide" of Altera.
> >
> > +config ROCKCHIP_EFUSE
> > + bool "Rockchip e-fuse support"
> > + depends on MISC
> > + help
> > + Enable (read-only) access for the e-fuse block found in Rockchip
> > + SoCs: accesses can either be made using byte addressing and a length
> > + or through child-nodes that are generated based on the e-fuse map
> > + retrieved from the DTS.
> > +
> > + This driver currently supports the RK3399 only, but can easily be
> > + extended (by porting the read function from the Linux kernel sources)
> > + to support other recent Rockchip devices.
> > +
> > config CMD_CROS_EC
> > bool "Enable crosec command"
> > depends on CROS_EC
> > @@ -167,4 +180,5 @@ config I2C_EEPROM
> > depends on MISC
> > help
> > Enable a generic driver for EEPROMs attached via I2C.
> > +
> > endmenu
> > diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
> > index e3151ea..77196fd 100644
> > --- a/drivers/misc/Makefile
> > +++ b/drivers/misc/Makefile
> > @@ -51,3 +51,4 @@ obj-$(CONFIG_PCA9551_LED) += pca9551_led.o
> > obj-$(CONFIG_FSL_DEVICE_DISABLE) += fsl_devdis.o
> > obj-$(CONFIG_WINBOND_W83627) += winbond_w83627.o
> > obj-$(CONFIG_QFW) += qfw.o
> > +obj-$(CONFIG_ROCKCHIP_EFUSE) += rockchip-efuse.o
> > diff --git a/drivers/misc/rockchip-efuse.c b/drivers/misc/rockchip-efuse.c
> > new file mode 100644
> > index 0000000..6eb3616
> > --- /dev/null
> > +++ b/drivers/misc/rockchip-efuse.c
> > @@ -0,0 +1,163 @@
> > +/*
> > + * eFuse driver for Rockchip devices
> > + *
> > + * Copyright 2017, Theobroma Systems Design und Consulting GmbH
> > + * Written by Philipp Tomsich <philipp.tomsich at theobroma-systems.com>
> > + *
> > + * SPDX-License-Identifier: GPL-2.0+
> > + */
> > +
> > +#define DEBUG
> > +
> > +#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;
> > +
> > + /* the first misc device will be used */
> > + ret = uclass_first_device_err(UCLASS_MISC, &dev);
>
> This might pick up a different device. Can you use
> uclass_get_device_by_driver() perhaps?
I've applied just the first patch in this series for now. Let me know
if you would rather keep the driver finding as you have it.
Regards,
Simon
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