soc: qcom: Add SoC info driver

The SoC info driver provides information such as Chip ID, Chip family, serial number and other such details about Qualcomm SoCs to user space, so that if needed some user space utility(like antutu) can query such information using sysfs interface.

---
v6 --> v7:
- Some minor style changes
- Rather than showing string for h/w types, just show the number obtained from SMEM. The reader of this number is supposed to parse this into a human readable string as this information may be different for different ODMs
- Create an attribute 'qcom_odm' depending on the presence of corresponding property in SMEM DT entry. This information can be used for ODM specific interpretation of SMEM socinfo content
- Read machine value from DT, rather than using soc-id as index in an ever increasing array of machine names

v5 --> v6:
- use dev_ext_attribute to represent SMEM image items
- Avoid redundant function calls
- Avoid use of unnecessary global variables
- Remove redundant enums
- Avoid redundant checking of socinfo being NULL or not
- Avoid redundant checking of socinfo format version
- Rename show/store function of attributes as _show/_store rather than _get/_set
- Use an array to represent socinfo attributes and create attribute files in a loop depending on the minimum socinfo format version for which these attributes are supported
- if obtained socinfo format version is greater than the maximum known version return an error rather than falling back to maximum known version

v4 --> v5:
- Removed redundant function socinfo_print

v3 --> v4:
- Corrected makefile so that smem and socinfo are treated as one module
- Moved the code snippet to get socinfo smem item into socinfo.c
- Removed redundant use of socinfo major version as it is always zero
- Removed unused enums
- Removed redundant indirections
- Use image_version object to store information about each entry in the smem image table
- Replaced usage of snprintf with sprintf and scnprintf
- Get the address of image version table at the beginning and setup image version attributes only if image version table is available
- Do the same for platform_subtype
- Make different type of image version objects read only or readable/ writable depending on their types. For example apps image attributes can be modified via sysfs but the same can't be done for modem image
- Show PMIC model in a human readable form rather than a numeric number
- Avoid using table in single sysfs entry
- Removed checkpatch warnings about S_IRUGO

v2 --> v3:
- Add support to toss soc information data into entropy pool
- Since socinfo is rolled into smem driver, compile the relevant portion of socinfo driver with smem driver

v1 --> v2:
- Removed inclusion of system_misc.h
- merged socinfo.h into socinfo.c
- made platform type and subtype arrays static
- replaced uint32_t with u32
- made functions static to avoid exposing vendor specific interface
- Replaced usage of IS_ERR_OR_NULL with IS_ERR.
- Remove raw-id attribute usage as human readable soc-id will suffice here
- Avoid using a separate platform driver for socinfo by rolling it into smem driver itself. The sysfs setup is being done in a separate file (socinfo.c)
- Replaced macro BUILD_ID_LENGTH with SMEM_SOCINFO_BUILD_ID_LENGTH.
- For failure cases where socinfo can not be read use a single dummy socinfo with error values.
- Removed usage of early_machine_is_xxx.

 drivers/soc/qcom/Kconfig   |   1 +
 drivers/soc/qcom/Makefile  |   3 +-
 drivers/soc/qcom/smem.c    |   5 +
 drivers/soc/qcom/socinfo.c | 515 +++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 523 insertions(+), 1 deletion(-)
 create mode 100644 drivers/soc/qcom/socinfo.c

index 461b387..f89d34d 100644
@@ -24,6 +24,7 @@ config QCOM_SMEM
 	tristate "Qualcomm Shared Memory Manager (SMEM)"
 	depends on ARCH_QCOM
 	depends on HWSPINLOCK
+	select SOC_BUS
 	help
 	  Say y here to enable support for the Qualcomm Shared Memory Manager.
 	  The driver provides an interface to items in a heap shared among all

index fdd664e..438efec 100644
@@ -2,7 +2,8 @@ obj-$(CONFIG_QCOM_GSBI)	+=	qcom_gsbi.o
 obj-$(CONFIG_QCOM_PM)	+=	spm.o
 obj-$(CONFIG_QCOM_SMD) +=	smd.o
 obj-$(CONFIG_QCOM_SMD_RPM)	+= smd-rpm.o
-obj-$(CONFIG_QCOM_SMEM) +=	smem.o
+obj-$(CONFIG_QCOM_SMEM) +=	qcom_smem.o
+qcom_smem-y := smem.o socinfo.o
 obj-$(CONFIG_QCOM_SMEM_STATE) += smem_state.o
 obj-$(CONFIG_QCOM_SMP2P)	+= smp2p.o
 obj-$(CONFIG_QCOM_SMSM)	+= smsm.o

index 18ec52f..4f0ccf8 100644
@@ -85,6 +85,9 @@
 /* Max number of processors/hosts in a system */
 #define SMEM_HOST_COUNT		9
 
+
+extern void qcom_socinfo_init(struct device *device);
+
 /**
   * struct smem_proc_comm - proc_comm communication struct (legacy)
   * @command:	current command to be executed

@@ -751,6 +754,8 @@ static int qcom_smem_probe(struct platform_device *pdev)
 
 	__smem = smem;
 
+	qcom_socinfo_init(&pdev->dev);
+
 	return 0;
 }
 

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