[PATCH v9 04/12] soc: samsung: add exynos chipid driver support

[pankaj.dubey]

On Friday 07 April 2017 02:43 PM, Krzysztof Kozlowski wrote:
> On Thu, Mar 30, 2017 at 3:16 PM, Pankaj Dubey <pankaj.dubey at samsung.com> wrote:
>> Exynos SoCs have Chipid, for identification of product IDs and SoC
>> revisions. This patch intends to provide initialization code for all
>> these functionalities, at the same time it provides some sysfs entries
>> for accessing these information to user-space.
>>
>> This driver uses existing binding for exynos-chipid.
>>
>> CC: Grant Likely <grant.likely at linaro.org>
>> CC: Rob Herring <robh+dt at kernel.org>
>> CC: Linus Walleij <linus.walleij at linaro.org>
>> Signed-off-by: Pankaj Dubey <pankaj.dubey at samsung.com>
>> [m.szyprowski: for suggestion and code snippet of product_id_to_soc_id]
>> Signed-off-by: Marek Szyprowski <m.szyprowski at samsung.com>
>> ---
>>  drivers/soc/samsung/Kconfig         |   5 ++
>>  drivers/soc/samsung/Makefile        |   1 +
>>  drivers/soc/samsung/exynos-chipid.c | 109 ++++++++++++++++++++++++++++++++++++
>>  3 files changed, 115 insertions(+)
>>  create mode 100644 drivers/soc/samsung/exynos-chipid.c
>>
>> diff --git a/drivers/soc/samsung/Kconfig b/drivers/soc/samsung/Kconfig
>> index 8b25bd5..a90a4ad 100644
>> --- a/drivers/soc/samsung/Kconfig
>> +++ b/drivers/soc/samsung/Kconfig
>> @@ -6,6 +6,11 @@ menuconfig SOC_SAMSUNG
>>
>>  if SOC_SAMSUNG
>>
>> +config EXYNOS_CHIPID
>> +       bool "Exynos Chipid controller driver" if COMPILE_TEST
>> +       depends on ARCH_EXYNOS || COMPILE_TEST
>> +       select SOC_BUS
>> +
>>  config EXYNOS_PMU
>>         bool "Exynos PMU controller driver" if COMPILE_TEST
>>         depends on ARCH_EXYNOS || ((ARM || ARM64) && COMPILE_TEST)
>> diff --git a/drivers/soc/samsung/Makefile b/drivers/soc/samsung/Makefile
>> index 4d7694a..be3b6bb 100644
>> --- a/drivers/soc/samsung/Makefile
>> +++ b/drivers/soc/samsung/Makefile
>> @@ -1,3 +1,4 @@
>> +obj-$(CONFIG_EXYNOS_CHIPID)    += exynos-chipid.o
>>  obj-$(CONFIG_EXYNOS_PMU)       += exynos-pmu.o
>>
>>  obj-$(CONFIG_EXYNOS_PMU_ARM_DRIVERS)   += exynos3250-pmu.o exynos4-pmu.o \
>> diff --git a/drivers/soc/samsung/exynos-chipid.c b/drivers/soc/samsung/exynos-chipid.c
>> new file mode 100644
>> index 0000000..1e9fb6b
>> --- /dev/null
>> +++ b/drivers/soc/samsung/exynos-chipid.c
>> @@ -0,0 +1,109 @@
>> +/*
>> + * Copyright (c) 2017 Samsung Electronics Co., Ltd.
>> + *           http://www.samsung.com/
>> + *
>> + * EXYNOS - CHIP ID support
>> + * Author: Pankaj Dubey <pankaj.dubey at samsung.com>
>> + *
>> + * This program is free software; you can redistribute it and/or modify
>> + * it under the terms of the GNU General Public License version 2 as
>> + * published by the Free Software Foundation.
>> + */
>> +
>> +#include <linux/io.h>
>> +#include <linux/of.h>
>> +#include <linux/of_address.h>
>> +#include <linux/of_platform.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/slab.h>
>> +#include <linux/sys_soc.h>
>> +
>> +#define EXYNOS_SUBREV_MASK     (0xF << 4)
>> +#define EXYNOS_MAINREV_MASK    (0xF << 0)
>> +#define EXYNOS_REV_MASK                (EXYNOS_SUBREV_MASK | EXYNOS_MAINREV_MASK)
>> +
>> +static const struct exynos_soc_id {
>> +       const char *name;
>> +       unsigned int id;
>> +       unsigned int mask;
>> +} soc_ids[] = {
>> +       { "EXYNOS3250", 0xE3472000, 0xFFFFF000 },
>> +       { "EXYNOS4210", 0x43210000, 0xFFFFF000 },
>> +       { "EXYNOS4212", 0x43220000, 0xFFFFF000 },
>> +       { "EXYNOS4412", 0xE4412000, 0xFFFFF000 },
>> +       { "EXYNOS5250", 0x43520000, 0xFFFFF000 },
>> +       { "EXYNOS5260", 0xE5260000, 0xFFFFF000 },
>> +       { "EXYNOS5410", 0xE5410000, 0xFFFFF000 },
>> +       { "EXYNOS5420", 0xE5420000, 0xFFFFF000 },
>> +       { "EXYNOS5440", 0xE5440000, 0xFFFFF000 },
>> +       { "EXYNOS5800", 0xE5422000, 0xFFFFF000 },
>> +       { "EXYNOS7420", 0xE7420000, 0xFFFFF000 },
>> +       { "EXYNOS5433", 0xE5433000, 0xFFFFF000 },
>> +};
>> +
>> +static const char * __init product_id_to_soc_id(unsigned int product_id)
>> +{
>> +       int i;
>> +
>> +       for (i = 0; i < ARRAY_SIZE(soc_ids); i++)
>> +               if ((product_id & soc_ids[i].mask) == soc_ids[i].id)
>> +                       return soc_ids[i].name;
>> +       return "UNKNOWN";
>> +}
>> +
>> +int __init exynos_chipid_early_init(void)
>> +{
>> +       struct soc_device_attribute *soc_dev_attr;
>> +       void __iomem *exynos_chipid_base;
>> +       struct soc_device *soc_dev;
>> +       struct device_node *root;
>> +       struct device_node *np;
>> +       struct device *dev;
>> +       u32 product_id;
>> +       u32 revision;
>> +
>> +       /* look up for chipid node */
>> +       np = of_find_compatible_node(NULL, NULL, "samsung,exynos4210-chipid");
>> +       if (!np)
>> +               return -ENODEV;
>> +
>> +       exynos_chipid_base = of_iomap(np, 0);
>> +       of_node_put(np);
>> +
>> +       if (!exynos_chipid_base) {
>> +               pr_err("%s: failed to map chipid\n", np->name);
>> +               return -ENOMEM;
>> +       }
>> +
>> +       product_id = readl_relaxed(exynos_chipid_base);
>> +       revision = product_id & EXYNOS_REV_MASK;
>> +       iounmap(exynos_chipid_base);
>> +
>> +       soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL);
>> +       if (!soc_dev_attr)
>> +               return -ENODEV;
> 
> This should be -ENOMEM
> 
OK. Will take care in next patchset.

>> +
>> +       soc_dev_attr->family = "Samsung Exynos";
>> +
>> +       root = of_find_node_by_path("/");
>> +       of_property_read_string(root, "model", &soc_dev_attr->machine);
>> +       of_node_put(root);
>> +
>> +       soc_dev_attr->revision = kasprintf(GFP_KERNEL, "%x", revision);
>> +       soc_dev_attr->soc_id = product_id_to_soc_id(product_id);
>> +
>> +       soc_dev = soc_device_register(soc_dev_attr);
>> +       if (IS_ERR(soc_dev)) {
>> +               kfree(soc_dev_attr->revision);
>> +               kfree_const(soc_dev_attr->soc_id);
> 
> This was not allocated with kstrdup_const() so it should not be freed.
> 

Sorry, I missed to take care of this, you pointed out this in V8 as well.

Thanks,
Pankaj Dubey
> Best regards,
> Krzysztof
> 
> 
>