[coreboot-gerrit] [S] Change in coreboot[main]: mb/google/rauru: Raise little core CPU frequency from 700MHz to 2.4GHz

[Yidi Lin (Code Review)]

Yidi Lin has submitted this change. ( https://review.coreboot.org/c/coreboot/+/85773?usp=email )

Change subject: mb/google/rauru: Raise little core CPU frequency from 700MHz to 2.4GHz
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mb/google/rauru: Raise little core CPU frequency from 700MHz to 2.4GHz

To improve boot time, raise little CPU from 700MHz to 2.4GHz at romstage
(before DRAM calibration).

FW logs:
Check CPU freq: 2400120 KHz

BUG=b:317009620
TEST=Build pass, boot ok.

Change-Id: I14a31f3a51ca246b842cc0ef740c43ff5d857310
Signed-off-by: Jarried Lin 
Reviewed-on: https://review.coreboot.org/c/coreboot/+/85773
Tested-by: build bot (Jenkins) 
Reviewed-by: Yidi Lin 
Reviewed-by: Yu-Ping Wu 
---
M src/mainboard/google/rauru/romstage.c
1 file changed, 10 insertions(+), 0 deletions(-)

Approvals:
  build bot (Jenkins): Verified
  Yidi Lin: Looks good to me, approved
  Yu-Ping Wu: Looks good to me, approved

diff --git a/src/mainboard/google/rauru/romstage.c b/src/mainboard/google/rauru/romstage.c
index af396a8..afd12c6 100644
--- a/src/mainboard/google/rauru/romstage.c
+++ b/src/mainboard/google/rauru/romstage.c
@@ -9,8 +9,17 @@
 #include <soc/mt6685.h>
 #include <soc/mtk_pwrsel.h>
 #include <soc/pcie.h>
+#include <soc/pll.h>
 #include <soc/pmif.h>

+static void raise_little_cpu_freq(void)
+{
+	mt6316_buck_set_voltage(SPMI_SLAVE_8, MT6316_BUCK_3, 1050000);
+	printk(BIOS_INFO, "%s: little core voltage: %d\n",
+	       __func__, mt6316_buck_get_voltage(SPMI_SLAVE_8, MT6316_BUCK_3));
+	mt_pll_raise_little_cpu_freq(2400U * MHz);
+}
+
 void platform_romstage_main(void)
 {
    irq2axi_disable();
@@ -20,6 +29,7 @@
    mt6363_enable_vtref18(true);
    mt6363_set_vtref18_voltage(1800000);
    mt6316_init();
+	raise_little_cpu_freq();
    mt6373_init();
    mt6685_init();
    mtk_dram_init();