From: Eduardo Valentin on
From: Eduardo Valentin <eduardo.valentin(a)>

This patch exports the OMAP3 IDCODE and Production ID to userspace
via /proc/socinfo.

Die ID is also exported depending on what users pass as kernel
parameter. It is same protection mechanism made for x86 product
number. So, if user passes "omap3_die_id" parameter, it will append
die id code into /proc/socinfo as well. A Kconfig option has been
added as well, so it can be configurable during compilation time.

This can be used to track down silicon specific issues. The info is
exported via /proc/socinfo because then it can be possible to include this
in corematic dumps.

This is based on Peter De Schrijver patch, which export same info via sysfs.

Signed-off-by: Eduardo Valentin <eduardo.valentin(a)>
Documentation/kernel-parameters.txt | 2 ++
arch/arm/mach-omap2/Kconfig | 10 ++++++++++
arch/arm/mach-omap2/id.c | 35 ++++++++++++++++++++++++++++++++++-
3 files changed, 46 insertions(+), 1 deletions(-)

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 839b21b..8010cfb 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1809,6 +1809,8 @@ and is between 256 and 4096 characters. It is defined in the file
waiting for the ACK, so if this is set too high
interrupts *may* be lost!

+ omap3_die_id [OMAP] Append DIE ID info under /proc/socinfo
omap_mux= [OMAP] Override bootloader pin multiplexing.
Format: <mux_mode0.mode_name=value>...
For example, to override I2C bus2:
diff --git a/arch/arm/mach-omap2/Kconfig b/arch/arm/mach-omap2/Kconfig
index 2455dcc..fb8abed 100644
--- a/arch/arm/mach-omap2/Kconfig
+++ b/arch/arm/mach-omap2/Kconfig
@@ -169,3 +169,13 @@ config OMAP3_SDRC_AC_TIMING
wish to say no. Selecting yes without understanding what is
going on could result in system crashes;

+ bool "Export DIE ID code under /proc/socinfo"
+ depends on ARCH_OMAP3
+ default n
+ help
+ Say Y here if you need DIE ID code to be exported via /proc/socinfo
+ in production systems. You will need also to explicitly flag it by
+ appending the "omap3_die_id" parameter to your boot command line.
diff --git a/arch/arm/mach-omap2/id.c b/arch/arm/mach-omap2/id.c
index 8ecd8e2..9663066 100644
--- a/arch/arm/mach-omap2/id.c
+++ b/arch/arm/mach-omap2/id.c
@@ -77,6 +77,10 @@ EXPORT_SYMBOL(omap_type);

#define OMAP_TAP_IDCODE 0x0204
+#define OMAP_TAP_PROD_ID_0 0x0208
+#define OMAP_TAP_PROD_ID_1 0x020c
+#define OMAP_TAP_PROD_ID_2 0x0210
+#define OMAP_TAP_PROD_ID_3 0x0214
#define OMAP_TAP_DIE_ID_0 0x0218
#define OMAP_TAP_DIE_ID_1 0x021C
#define OMAP_TAP_DIE_ID_2 0x0220
@@ -305,6 +309,7 @@ void __init omap4_check_revision(void)

void __init omap3_cpuinfo(void)
+ int sz;
char cpu_name[16], cpu_rev[16];

@@ -362,7 +367,7 @@ void __init omap3_cpuinfo(void)

/* Print verbose information */
- snprintf(socinfo, SOCINFO_SZ, "%s ES%s", cpu_name, cpu_rev);
+ sz = snprintf(socinfo, SOCINFO_SZ, "%s ES%s", cpu_name, cpu_rev);
pr_info("%s (", socinfo);

@@ -373,7 +378,35 @@ void __init omap3_cpuinfo(void)

+ /* Append OMAP3 IDCODE and Production ID to system_soc_info */
+ snprintf(socinfo + sz, SOCINFO_SZ - sz,
+ "\nIDCODE\t: %08x\nPr. ID\t: %08x %08x %08x %08x",
+ read_tap_reg(OMAP_TAP_IDCODE),
+ read_tap_reg(OMAP_TAP_PROD_ID_0),
+ read_tap_reg(OMAP_TAP_PROD_ID_1),
+ read_tap_reg(OMAP_TAP_PROD_ID_2),
+ read_tap_reg(OMAP_TAP_PROD_ID_3));
+static int __init omap3_die_id_setup(char *s)
+ int sz;
+ sz = strlen(socinfo);
+ snprintf(socinfo + sz, SOCINFO_SZ - sz,
+ "\nDie ID\t: %08x %08x %08x %08x",
+ read_tap_reg(OMAP_TAP_DIE_ID_0),
+ read_tap_reg(OMAP_TAP_DIE_ID_1),
+ read_tap_reg(OMAP_TAP_DIE_ID_2),
+ read_tap_reg(OMAP_TAP_DIE_ID_3));
+ return 1;
+__setup("omap3_die_id", omap3_die_id_setup);

* Try to detect the exact revision of the omap we're running on

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