[PATCH 1/2] ARM: meson: Adding support to retrieve serial and SoC revision
From: Carlo Caione <hidden>
Date: 2016-02-17 20:34:52
Also in:
linux-devicetree
On Wed, Feb 17, 2016 at 6:28 PM, Romain Perier [off-list ref] wrote:
This path adds support to get the revision and the serial of the running SoC, on Meson8. On these plaforms, these informations can be found into
no Meson8b or Meson6?
CBUS registers. To do so, we instanciate a syscon register, then create
What you mean with syscon register?
quoted hunk
a soc_device, and finally we expose everything to the system. Signed-off-by: Romain Perier <romain.perier@gmail.com> --- arch/arm/mach-meson/meson.c | 55 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 55 insertions(+)diff --git a/arch/arm/mach-meson/meson.c b/arch/arm/mach-meson/meson.c index 4e23571..2816e30 100644 --- a/arch/arm/mach-meson/meson.c +++ b/arch/arm/mach-meson/meson.c@@ -13,8 +13,16 @@ * */ +#include <linux/of_address.h> #include <linux/of_platform.h> +#include <linux/mfd/syscon.h> +#include <linux/regmap.h> +#include <linux/slab.h> +#include <linux/sys_soc.h> #include <asm/mach/arch.h> +#include <asm/system_info.h> + +#define MESON_REVISION_REG (0x45c) static const char * const meson_common_board_compat[] = { "amlogic,meson6",@@ -23,7 +31,54 @@ static const char * const meson_common_board_compat[] = { NULL, }; +static void __init meson_init_machine(void) +{ + struct soc_device_attribute *soc_dev_attr; + struct soc_device *soc_dev; + struct regmap *hwrev; + unsigned int val; + int ret; + + hwrev = syscon_regmap_lookup_by_compatible("amlogic,meson8b-hwrev");
Is this specific only for Meson8b?
+ if (IS_ERR(hwrev)) {
+ pr_err("hwrev node not found\n");
+ return;
+ }
+
+ soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL);
+ if (!soc_dev_attr)
+ return;Missing blank line
+ ret = regmap_read(hwrev, 0, &val);
+ if (ret < 0) {
+ pr_err("Could not get SoC id\n");kfree(soc_dev_attr)
+ return;
+ }
+ system_serial_high = val << 24;
+
+ ret = regmap_read(hwrev, MESON_REVISION_REG, &val);
+ if (ret < 0) {
+ pr_err("Could not get SoC revision\n");ditto
+ return;
+ }
+ system_rev = val == 0x11111111 ? 0xA : 0xB;
+
+ soc_dev_attr->family = "Amlogic Meson";
+ soc_dev_attr->revision = kasprintf(GFP_KERNEL, "0x%x", system_rev);
+ soc_dev_attr->soc_id = kasprintf(GFP_KERNEL, "0x%x", system_serial_high);
+
+ soc_dev = soc_device_register(soc_dev_attr);
+ if (IS_ERR(soc_dev)) {
+ pr_err("Could not register soc device\n");
+ kfree(soc_dev_attr);leaking soc_dev_attr->revision and soc_dev_attr->soc_id also any reason why you are not kasprintf-ing also family?
+ return;
+ }
+
+ pr_info("Amlogic Meson SoC Rev%X (%X:%X)\n", system_rev, system_serial_high, system_rev);
+ of_platform_populate(NULL, of_default_bus_match_table, NULL, soc_dev);
Compiling I got:
CC arch/arm/mach-meson/meson.o
arch/arm/mach-meson/meson.c: In function 'meson_init_machine':
arch/arm/mach-meson/meson.c:77:63: warning: passing argument 4 of
'of_platform_populate' from incompatible pointer type
of_platform_populate(NULL, of_default_bus_match_table, NULL, soc_dev);
^
In file included from arch/arm/mach-meson/meson.c:17:0:
include/linux/of_platform.h:71:12: note: expected 'struct device *'
but argument is of type 'struct soc_device *'
extern int of_platform_populate(struct device_node *root,
^
+} + DT_MACHINE_START(MESON, "Amlogic Meson platform") + .init_machine = meson_init_machine,
Uhm, you are assuming that this code is valid for Meson8, Meson8b and also Meson6. Are you sure about that?
.dt_compat = meson_common_board_compat,
.l2c_aux_val = 0,
.l2c_aux_mask = ~0,
--
2.5.0Thanks for working on this! -- Carlo Caione