Re: [U-Boot] [PATCH] ARMV7: Overo: Automatically set clock rate to maximum if mpurate env variable is auto
-Original Message- From: u-boot-boun...@lists.denx.de [mailto:u-boot-boun...@lists.denx.de] On Behalf Of Wolfgang Denk Sent: Monday, November 08, 2010 3:14 AM To: Steve Sakoman Cc: u-boot@lists.denx.de Subject: Re: [U-Boot] [PATCH] ARMV7: Overo: Automatically set clock rate to maximum if mpurate env variable is auto Dear Steve Sakoman, In message 1289012370.18546.66.ca...@quadra you wrote: The maximum clock rate for the OMAP3 processors on Overo depends on the processor type and revision. This patch sets the clock rate to the spec sheet maximum if the mpurate environment variable is set to auto. Otherwise it passes the mpurate variable unchanged on the kernel command line. I don't think this is a good idea. This logic does not belong into U-Boot; if anywhere, it belongs into the Linux kernel code. If I want to pass any specific value to the Linux kernel I want that U-Boot does not get in my way. And if I decide to set the mpurate to auto I want that U-Boot keeps this setting and does not change it silently behind my back into something else. [sp] I am in full agreement. It is too difficult to find root cause for transparent changes - usually lead to long debug times first in kernel an then in u-boot. ~sanjeev Both looks conceptually broken to me. Best regards, Wolfgang Denk -- DENX Software Engineering GmbH, MD: Wolfgang Denk Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: w...@denx.de It became apparent that one reason why the Ice Giants were known as the Ice Giants was because they were, well, giants. The other was that they were made of ice. -Terry Pratchett, _Sourcery_ ___ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot ___ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
Re: [U-Boot] [PATCH] ARMV7: Overo: Automatically set clock rate to maximum if mpurate env variable is auto
Dear Steve Sakoman, In message 1289012370.18546.66.ca...@quadra you wrote: The maximum clock rate for the OMAP3 processors on Overo depends on the processor type and revision. This patch sets the clock rate to the spec sheet maximum if the mpurate environment variable is set to auto. Otherwise it passes the mpurate variable unchanged on the kernel command line. I don't think this is a good idea. This logic does not belong into U-Boot; if anywhere, it belongs into the Linux kernel code. If I want to pass any specific value to the Linux kernel I want that U-Boot does not get in my way. And if I decide to set the mpurate to auto I want that U-Boot keeps this setting and does not change it silently behind my back into something else. Both looks conceptually broken to me. Best regards, Wolfgang Denk -- DENX Software Engineering GmbH, MD: Wolfgang Denk Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: w...@denx.de It became apparent that one reason why the Ice Giants were known as the Ice Giants was because they were, well, giants. The other was that they were made of ice. -Terry Pratchett, _Sourcery_ ___ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
[U-Boot] [PATCH] ARMV7: Overo: Automatically set clock rate to maximum if mpurate env variable is auto
The maximum clock rate for the OMAP3 processors on Overo depends on the
processor type and revision. This patch sets the clock rate to the
spec sheet maximum if the mpurate environment variable is set to
auto. Otherwise it passes the mpurate variable unchanged on the
kernel command line.
Signed-off-by: Steve Sakoman steve.sako...@linaro.org
---
diff --git a/board/overo/overo.c b/board/overo/overo.c
index f917e40..3c9e4a6 100644
--- a/board/overo/overo.c
+++ b/board/overo/overo.c
@@ -281,6 +281,22 @@ int misc_init_r(void)
dieid_num_r();
+ if (strcmp(getenv(mpurate), auto) == 0)
+ switch (get_cpu_family()) {
+ case CPU_OMAP34XX:
+ if ((get_cpu_rev() = CPU_3XX_ES31)
+ (get_sku_id() == SKUID_CLK_720MHZ))
+ setenv(mpurate, 720);
+ else
+ setenv(mpurate, 600);
+ break;
+ case CPU_OMAP36XX:
+ setenv(mpurate, 720);
+ break;
+ default:
+ setenv(mpurate, 500);
+ }
+
return 0;
}
diff --git a/include/configs/omap3_overo.h b/include/configs/omap3_overo.h
index 79a5b85..dbdfd9a 100644
--- a/include/configs/omap3_overo.h
+++ b/include/configs/omap3_overo.h
@@ -156,7 +156,7 @@
#define CONFIG_EXTRA_ENV_SETTINGS \
loadaddr=0x8200\0 \
console=ttyS2,115200n8\0 \
- mpurate=500\0 \
+ mpurate=auto\0 \
vram=12M\0 \
dvimode=1024x768mr...@60\0 \
defaultdisplay=dvi\0 \
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Re: [U-Boot] [PATCH] ARMV7: Overo: Automatically set clock rate to maximum if mpurate env variable is auto
just a minor crib - $subject length is around 88 characters, it'd look
better with around 50 character length.
Steve Sakoman wrote, on 11/05/2010 10:59 PM:
The maximum clock rate for the OMAP3 processors on Overo depends on the
processor type and revision. This patch sets the clock rate to the
spec sheet maximum if the mpurate environment variable is set to
auto. Otherwise it passes the mpurate variable unchanged on the
kernel command line.
Signed-off-by: Steve Sakomansteve.sako...@linaro.org
---
diff --git a/board/overo/overo.c b/board/overo/overo.c
index f917e40..3c9e4a6 100644
--- a/board/overo/overo.c
+++ b/board/overo/overo.c
@@ -281,6 +281,22 @@ int misc_init_r(void)
dieid_num_r();
+ if (strcmp(getenv(mpurate), auto) == 0)
+ switch (get_cpu_family()) {
+ case CPU_OMAP34XX:
+ if ((get_cpu_rev()= CPU_3XX_ES31)
+ (get_sku_id() == SKUID_CLK_720MHZ))
+ setenv(mpurate, 720);
+ else
+ setenv(mpurate, 600);
+ break;
+ case CPU_OMAP36XX:
+ setenv(mpurate, 720);
+ break;
+ default:
+ setenv(mpurate, 500);
+ }
+
return 0;
}
diff --git a/include/configs/omap3_overo.h b/include/configs/omap3_overo.h
index 79a5b85..dbdfd9a 100644
--- a/include/configs/omap3_overo.h
+++ b/include/configs/omap3_overo.h
@@ -156,7 +156,7 @@
#define CONFIG_EXTRA_ENV_SETTINGS \
loadaddr=0x8200\0 \
console=ttyS2,115200n8\0 \
- mpurate=500\0 \
+ mpurate=auto\0 \
vram=12M\0 \
dvimode=1024x768mr...@60\0 \
defaultdisplay=dvi\0 \
yep, this does look like a nice way to do it. thanks.
--
Regards,
Nishanth Menon
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