| Message ID | 27733a88b73adb7000205e020bafdb6f7ebe1843.1432099651.git.maitysanchayan@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wednesday 20 May 2015 11:06:52 Sanchayan Maity wrote: > Implements SoC bus support to export SoC specific information. Read > the unique SoC ID from the Vybrid On Chip One Time Programmable > (OCOTP) controller, SoC specific information from the Miscellaneous > System Control Module (MSCM), revision from the ROM revision register > and expose it via the SoC bus infrastructure. > > Sample Output: > > root@vf:/sys/devices/soc0# cat soc_id > df63c12a2e2161d4 > root@vf:/sys/devices/soc0# cat family > Freescale Vybrid VF500 > root@vf:/sys/devices/soc0# cat revision > 00000013 > root@vf:/sys/devices/soc0# cat machine > Freescale Vybrid > I would prefer to see this as a driver in drivers/soc that registers to a platform device. Is there any DT node that would be a reasonable device to bind to? Arnd
On 2015-05-20 09:12, Arnd Bergmann wrote: > On Wednesday 20 May 2015 11:06:52 Sanchayan Maity wrote: >> Implements SoC bus support to export SoC specific information. Read >> the unique SoC ID from the Vybrid On Chip One Time Programmable >> (OCOTP) controller, SoC specific information from the Miscellaneous >> System Control Module (MSCM), revision from the ROM revision register >> and expose it via the SoC bus infrastructure. >> >> Sample Output: >> >> root@vf:/sys/devices/soc0# cat soc_id >> df63c12a2e2161d4 >> root@vf:/sys/devices/soc0# cat family >> Freescale Vybrid VF500 >> root@vf:/sys/devices/soc0# cat revision >> 00000013 >> root@vf:/sys/devices/soc0# cat machine >> Freescale Vybrid >> > > I would prefer to see this as a driver in drivers/soc that registers > to a platform device. Is there any DT node that would be a reasonable > device to bind to? Hm, what is a viable device? Probably the most SoC specific device in the SoC? Currently, all three devices we read from do have a vf610-something compatible string, hence would be SoC specific (ocotp, ocrom and mscm-cpucfg). Probably the last is the most SoC specific... But somehow bind to just a random device sounds wrong to me. Couldn't we add a more specific compatible string to the soc node and bind to that? -- Stefan
On Wednesday 20 May 2015 09:36:38 Stefan Agner wrote: > On 2015-05-20 09:12, Arnd Bergmann wrote: > > On Wednesday 20 May 2015 11:06:52 Sanchayan Maity wrote: > >> Implements SoC bus support to export SoC specific information. Read > >> the unique SoC ID from the Vybrid On Chip One Time Programmable > >> (OCOTP) controller, SoC specific information from the Miscellaneous > >> System Control Module (MSCM), revision from the ROM revision register > >> and expose it via the SoC bus infrastructure. > >> > >> Sample Output: > >> > >> root@vf:/sys/devices/soc0# cat soc_id > >> df63c12a2e2161d4 > >> root@vf:/sys/devices/soc0# cat family > >> Freescale Vybrid VF500 > >> root@vf:/sys/devices/soc0# cat revision > >> 00000013 > >> root@vf:/sys/devices/soc0# cat machine > >> Freescale Vybrid > >> > > > > I would prefer to see this as a driver in drivers/soc that registers > > to a platform device. Is there any DT node that would be a reasonable > > device to bind to? > > Hm, what is a viable device? Probably the most SoC specific device in > the SoC? Currently, all three devices we read from do have a > vf610-something compatible string, hence would be SoC specific (ocotp, > ocrom and mscm-cpucfg). Probably the last is the most SoC specific... > > But somehow bind to just a random device sounds wrong to me. Couldn't we > add a more specific compatible string to the soc node and bind to that? mscm-cpucfg by the name sounds right to me, especially if we later want to add some exported functions or configuration to the driver. The other two (judging by the name without knowing anything about them) seem like pure data areas that may also be shared with other drivers and are better represented as syscon or eprom devices. Arnd
diff --git a/arch/arm/mach-imx/mach-vf610.c b/arch/arm/mach-imx/mach-vf610.c index 2e7c75b..b4854f1 100644 --- a/arch/arm/mach-imx/mach-vf610.c +++ b/arch/arm/mach-imx/mach-vf610.c @@ -7,10 +7,90 @@ * (at your option) any later version. */ -#include <linux/of_platform.h> -#include <linux/irqchip.h> #include <asm/mach/arch.h> #include <asm/hardware/cache-l2x0.h> +#include <linux/irqchip.h> +#include <linux/mfd/syscon.h> +#include <linux/of_platform.h> +#include <linux/regmap.h> +#include <linux/random.h> +#include <linux/slab.h> +#include <linux/sys_soc.h> + +#define OCOTP_CFG0_OFFSET 0x00000410 +#define OCOTP_CFG1_OFFSET 0x00000420 +#define MSCM_CPxCOUNT_OFFSET 0x0000002C +#define MSCM_CPxCFG1_OFFSET 0x00000014 +#define ROM_REVISION_OFFSET 0x00000080 + +static void __init vf610_init_machine(void) +{ + struct regmap *ocotp_regmap, *mscm_regmap, *rom_regmap; + struct soc_device_attribute *soc_dev_attr; + struct device *parent = NULL; + struct soc_device *soc_dev; + char soc_type[] = "xx0"; + u32 cpxcount, cpxcfg1; + u32 soc_id1, soc_id2, rom_rev; + u64 soc_id; + + ocotp_regmap = syscon_regmap_lookup_by_compatible("fsl,vf610-ocotp"); + if (IS_ERR(ocotp_regmap)) { + pr_err("regmap lookup for octop failed\n"); + goto out; + } + + mscm_regmap = syscon_regmap_lookup_by_compatible("fsl,vf610-mscm-cpucfg"); + if (IS_ERR(mscm_regmap)) { + pr_err("regmap lookup for mscm failed"); + goto out; + } + + rom_regmap = syscon_regmap_lookup_by_compatible("fsl,vf610-ocrom"); + if (IS_ERR(rom_regmap)) { + pr_err("regmap lookup for ocrom failed"); + goto out; + } + + regmap_read(ocotp_regmap, OCOTP_CFG0_OFFSET, &soc_id1); + regmap_read(ocotp_regmap, OCOTP_CFG1_OFFSET, &soc_id2); + + soc_id = (u64) soc_id1 << 32 | soc_id2; + add_device_randomness(&soc_id, sizeof(soc_id)); + + regmap_read(mscm_regmap, MSCM_CPxCOUNT_OFFSET, &cpxcount); + regmap_read(mscm_regmap, MSCM_CPxCFG1_OFFSET, &cpxcfg1); + + soc_type[0] = cpxcount ? '6' : '5'; /* Dual Core => VF6x0 */ + soc_type[1] = cpxcfg1 ? '1' : '0'; /* L2 Cache => VFx10 */ + + regmap_read(rom_regmap, ROM_REVISION_OFFSET, &rom_rev); + + soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL); + if (!soc_dev_attr) + goto out; + + soc_dev_attr->machine = kasprintf(GFP_KERNEL, "Freescale Vybrid"); + soc_dev_attr->soc_id = kasprintf(GFP_KERNEL, "%016llx", soc_id); + soc_dev_attr->family = kasprintf(GFP_KERNEL, "Freescale Vybrid VF%s", + soc_type); + soc_dev_attr->revision = kasprintf(GFP_KERNEL, "%08x", rom_rev); + + soc_dev = soc_device_register(soc_dev_attr); + if (IS_ERR(soc_dev)) { + kfree(soc_dev_attr->revision); + kfree(soc_dev_attr->family); + kfree(soc_dev_attr->soc_id); + kfree(soc_dev_attr->machine); + kfree(soc_dev_attr); + goto out; + } + + parent = soc_device_to_device(soc_dev); + +out: + of_platform_populate(NULL, of_default_bus_match_table, NULL, parent); +} static const char * const vf610_dt_compat[] __initconst = { "fsl,vf500", @@ -23,5 +103,6 @@ static const char * const vf610_dt_compat[] __initconst = { DT_MACHINE_START(VYBRID_VF610, "Freescale Vybrid VF5xx/VF6xx (Device Tree)") .l2c_aux_val = 0, .l2c_aux_mask = ~0, + .init_machine = vf610_init_machine, .dt_compat = vf610_dt_compat, MACHINE_END
Implements SoC bus support to export SoC specific information. Read the unique SoC ID from the Vybrid On Chip One Time Programmable (OCOTP) controller, SoC specific information from the Miscellaneous System Control Module (MSCM), revision from the ROM revision register and expose it via the SoC bus infrastructure. Sample Output: root@vf:/sys/devices/soc0# cat soc_id df63c12a2e2161d4 root@vf:/sys/devices/soc0# cat family Freescale Vybrid VF500 root@vf:/sys/devices/soc0# cat revision 00000013 root@vf:/sys/devices/soc0# cat machine Freescale Vybrid Signed-off-by: Sanchayan Maity <maitysanchayan@gmail.com> --- arch/arm/mach-imx/mach-vf610.c | 85 +++++++++++++++++++++++++++++++++++++++++- 1 file changed, 83 insertions(+), 2 deletions(-)