diff options
author | Ionela Voinescu <ionela.voinescu@imgtec.com> | 2015-01-19 02:41:49 +0000 |
---|---|---|
committer | Patrick Georgi <pgeorgi@google.com> | 2015-03-21 11:09:22 +0100 |
commit | 367331161995e7cbaa507bd24a71a28bc97c4834 (patch) | |
tree | 3b5ebc236027fe4f9861ba528c791a44d9e56171 /payloads/libpayload/arch | |
parent | bde2081e753b90734af9f198b1ae84d26930363d (diff) |
libpayload: mips: add SOC CPU frequency
Add CPU frequency corresponding to SOC.
BUG=chrome-os-partner:31438
TEST=tested on Pistachio bring up board; behaves as expected.
BRANCH=none
Change-Id: I05458070a15c6cf1ef0fc2104715a63902a38887
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: 4afe332bcc41afeb7e31e918e345c3336f7dc604
Original-Change-Id: I55b788faf7984bafc2509cac69867a772c7cb863
Original-Signed-off-by: Ionela Voinescu <ionela.voinescu@imgtec.com>
Original-Reviewed-on: https://chromium-review.googlesource.com/241427
Original-Reviewed-by: David Hendricks <dhendrix@chromium.org>
Reviewed-on: http://review.coreboot.org/8853
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
Diffstat (limited to 'payloads/libpayload/arch')
-rw-r--r-- | payloads/libpayload/arch/mips/timer.c | 21 |
1 files changed, 17 insertions, 4 deletions
diff --git a/payloads/libpayload/arch/mips/timer.c b/payloads/libpayload/arch/mips/timer.c index 1710a322e2..782959b71a 100644 --- a/payloads/libpayload/arch/mips/timer.c +++ b/payloads/libpayload/arch/mips/timer.c @@ -19,6 +19,10 @@ #include <libpayload.h> #include <arch/cpu.h> +#include <arch/io.h> + +#define PISTACHIO_CLOCK_SWITCH 0xB8144200 +#define MIPS_EXTERN_PLL_BYPASS_MASK 0x00000002 /** * @ingroup arch @@ -34,10 +38,19 @@ u32 cpu_khz; unsigned int get_cpu_speed(void) { if (IMG_PLATFORM_ID() != IMG_PLATFORM_ID_SILICON) - cpu_khz = 50000U; /* FPGA board */ - /* else { - * TODO find CPU frequency on the real SOC - } */ + cpu_khz = 50000; /* FPGA board */ + else { + /* If MIPS PLL external bypass bit is set, it means + * that the MIPS PLL is already set up to work at a + * frequency of 550 MHz; otherwise, the crystal is + * used with a frequency of 52 MHz + */ + if (read32(PISTACHIO_CLOCK_SWITCH) & + MIPS_EXTERN_PLL_BYPASS_MASK) + cpu_khz = 550000; + else + cpu_khz = 52000; + } return cpu_khz; } |