On Wednesday 06 May 2015 12:37:52 Pali Rohár wrote: > On Wednesday 06 May 2015 11:31:15 Arnd Bergmann wrote: > > On Wednesday 06 May 2015 10:49:01 Pali Rohár wrote: > > > With this patch "revision" DT string entry is used to set global system_rev > > > variable. DT "revision" is expected to be string with one hexadecimal number. > > > So "Revision" line in /proc/cpuinfo will be same as "revision" DT value. > > > > > > Signed-off-by: Pali Rohár <pali.rohar@xxxxxxxxx> > > > Acked-by: Pavel Machek <pavel@xxxxxx> > > > > +devicetree mailing list > > > > The property needs to be specified in a binding somewhere. > > > > > @@ -246,5 +247,14 @@ const struct machine_desc * __init setup_machine_fdt(unsigned int dt_phys) > > > /* Change machine number to match the mdesc we're using */ > > > __machine_arch_type = mdesc->nr; > > > > > > + /* Set system revision from DT */ > > > + prop = of_get_flat_dt_prop(dt_root, "revision", &size); > > > + if (prop && size > 0) { > > > + char revision[11]; > > > + strlcpy(revision, prop, min(size, (int)sizeof(revision))); > > > + if (kstrtouint(revision, 16, &system_rev) != 0) > > > + system_rev = 0; > > > + } > > > + > > > return mdesc; > > > } > > > > > > > What is the reason for doing it this early? I think it would be nicer to do > > it after unflattening the DT. > > > > It needs to be done in this code, so "system_rev" variable is set > properly... What I mean is which code accesses this variable that early? > > Also, it seems strange to have a string property and then use kstrtouint > > to convert it into a number. I think it should either be specified in a DT > > binding to be a string and then have the kernel not assume that it is a number, > > or we should define it to be binary. > > > > Arnd > > Variable "system_rev" is number and it always was. So chaning type will > break more parts. > > And it is string DT property to be human readable. Some other developers > suggested for v2 to change it to string (from number). Both of them would be human readable, you just use something else to read them ;-) If we have a string here, we should just change all uses of system_rev in the kernel accordingly, there are only a few of them: $ git grep -w system_rev arch/arm/include/asm/system_info.h:extern unsigned int system_rev; arch/arm/kernel/atags_parse.c: system_rev = tag->u.revision.rev; arch/arm/kernel/setup.c:unsigned int system_rev; arch/arm/kernel/setup.c:EXPORT_SYMBOL(system_rev); arch/arm/kernel/setup.c: seq_printf(m, "Revision\t: %04x\n", system_rev); arch/arm/mach-clps711x/devices.c: system_rev = SYSFLG1_VERID(readl(base + SYSFLG1)); arch/arm/mach-clps711x/devices.c: soc_dev_attr->revision = kasprintf(GFP_KERNEL, "%u", system_rev); arch/arm/mach-davinci/board-da850-evm.c: switch (system_rev & 0xF) { arch/arm/mach-imx/mach-imx27_visstrim_m10.c: system_rev = 0x27000; arch/arm/mach-imx/mach-imx27_visstrim_m10.c: system_rev |= (mo_version << MOTHERBOARD_SHIFT); arch/arm/mach-imx/mach-imx27_visstrim_m10.c: system_rev |= (exp_version << EXPBOARD_SHIFT); arch/arm/mach-imx/mach-imx27_visstrim_m10.c: mo_version = (system_rev >> MOTHERBOARD_SHIFT) & VERSION_MASK; arch/arm/mach-ixp4xx/goramo_mlr.c: system_rev = __raw_readl(flash + CFG_REV); arch/arm/mach-omap2/board-rx51-peripherals.c: if ((system_rev >= SYSTEM_REV_S_USES_VAUX3 && system_rev < 0x100) || arch/arm/mach-omap2/board-rx51-peripherals.c: system_rev >= SYSTEM_REV_B_USES_VAUX3) { arch/arm/mach-orion5x/dns323-setup.c: if (machine_is_dns323() && system_rev == DNS323_REV_A1) arch/arm/mach-orion5x/dns323-setup.c: system_rev = dns323_identify_rev(); arch/arm/mach-orion5x/dns323-setup.c: pr_info("DNS-323: Identified HW revision %c1\n", 'A' + system_rev); arch/arm/mach-orion5x/dns323-setup.c: switch(system_rev) { arch/arm/mach-orion5x/dns323-setup.c: switch(system_rev) { arch/arm/mach-orion5x/dns323-setup.c: switch(system_rev) { arch/arm/mach-pxa/cm-x300.c: if (system_rev < 130) arch/arm/mach-pxa/cm-x300.c: if (system_rev < 130) { arch/arm/mach-pxa/cm-x300.c: if (system_rev < 130) arch/arm/mach-pxa/magician.c: if (system_rev < 3) arch/arm/mach-pxa/magician.c: if (system_rev < 3) arch/arm/mach-pxa/magician.c: system_rev = board_id & 0x7; arch/arm/mach-pxa/magician.c: if (lcd_select && (system_rev < 3)) arch/arm/mach-pxa/raumfeld.c: if ((system_rev & 0xff) == 2) { arch/arm/mach-pxa/raumfeld.c: if ((system_rev & 0xff) > 1) { arch/arm/mach-pxa/viper.c: system_rev = (VIPER_BOARD_VERSION(version) << 8) | arch/arm/mach-pxa/zeus.c: system_rev = __raw_readw(ZEUS_CPLD_VERSION); arch/arm/mach-pxa/zeus.c: pr_info("Zeus CPLD V%dI%d\n", (system_rev & 0xf0) >> 4, (system_rev & 0x0f)); arch/arm/mach-zynq/common.c: system_rev = zynq_get_revision(); arch/arm/mach-zynq/common.c: soc_dev_attr->revision = kasprintf(GFP_KERNEL, "0x%x", system_rev); In fact, half the uses of this actually assign the revision number themselves. code outside of arch/arm/mach-* and /proc/cpuinfo currently uses the variable. Arnd -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html