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[U-Boot,2/2] sunxi: defconfig: Sunchip CX-A99: Raise CPU voltage and clock frequency

Message ID 2422a0c97dd71c6a0473471e13891668363f0ee4.1488128420.git.rask@formelder.dk
State Changes Requested
Delegated to: Jaehoon Chung
Headers show

Commit Message

Rask Ingemann Lambertsen Feb. 26, 2017, 7:02 p.m. UTC
This patch uses the AXP808 support to raise the Cortex-A7 core voltage
from the power-on default of 0.9 V to 1.02 V and increases the clock
frequency from the default 1008 MHz to 1200 MHz. This is the maximum clock
frequency listed in the vendor's sys_config.fex file.

Signed-off-by: Rask Ingemann Lambertsen <rask@formelder.dk>
---
This patch goes on top of "ARM: sunxi: Add defconfig for Sunchip CX-A99".

FWIW, I seem to get away with

CONFIG_SYS_CLK_FREQ=1296000000
CONFIG_AXP_DCDCA_VOLT=1100

but neither "Allwinner UltraOcta A80 Datasheet" (revision 1.3) nor 
"Allwinner A80 User Manual" (revision 1.3.1) say anything about the
supported clock frequencies.

 configs/Sunchip_CX-A99_defconfig | 2 ++
 1 file changed, 2 insertions(+)

Comments

Chen-Yu Tsai Feb. 27, 2017, 3:08 a.m. UTC | #1
On Mon, Feb 27, 2017 at 3:02 AM, Rask Ingemann Lambertsen
<rask@formelder.dk> wrote:
> This patch uses the AXP808 support to raise the Cortex-A7 core voltage
> from the power-on default of 0.9 V to 1.02 V and increases the clock
> frequency from the default 1008 MHz to 1200 MHz. This is the maximum clock
> frequency listed in the vendor's sys_config.fex file.

This should really be left to a proper cpufreq/DVFS system. The bootloader
should bring up the system in a safe, usable state.

1008 MHz is the default across all Allwinner SoCs, aside from a few boards
that cannot reach it without overvoltage. It's even the default in BSP
bootloaders.


ChenYu

>
> Signed-off-by: Rask Ingemann Lambertsen <rask@formelder.dk>
> ---
> This patch goes on top of "ARM: sunxi: Add defconfig for Sunchip CX-A99".
>
> FWIW, I seem to get away with
>
> CONFIG_SYS_CLK_FREQ=1296000000
> CONFIG_AXP_DCDCA_VOLT=1100
>
> but neither "Allwinner UltraOcta A80 Datasheet" (revision 1.3) nor
> "Allwinner A80 User Manual" (revision 1.3.1) say anything about the
> supported clock frequencies.
>
>  configs/Sunchip_CX-A99_defconfig | 2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/configs/Sunchip_CX-A99_defconfig b/configs/Sunchip_CX-A99_defconfig
> index 7530d7d..3b760d8 100644
> --- a/configs/Sunchip_CX-A99_defconfig
> +++ b/configs/Sunchip_CX-A99_defconfig
> @@ -4,6 +4,7 @@ CONFIG_MACH_SUN9I=y
>  CONFIG_DRAM_CLK=600
>  CONFIG_DRAM_ZQ=3881915
>  CONFIG_DRAM_ODT_EN=y
> +CONFIG_SYS_CLK_FREQ=1200000000
>  CONFIG_MMC0_CD_PIN="PH17"
>  CONFIG_MMC_SUNXI_SLOT_EXTRA=2
>  CONFIG_USB0_VBUS_PIN="PH15"
> @@ -17,6 +18,7 @@ CONFIG_SPL=y
>  # CONFIG_CMD_IMLS is not set
>  # CONFIG_CMD_FLASH is not set
>  # CONFIG_CMD_FPGA is not set
> +CONFIG_AXP_DCDCA_VOLT=1020
>  # CONFIG_SPL_DOS_PARTITION is not set
>  # CONFIG_SPL_ISO_PARTITION is not set
>  # CONFIG_SPL_EFI_PARTITION is not set
> --
> 2.10.2
>
diff mbox

Patch

diff --git a/configs/Sunchip_CX-A99_defconfig b/configs/Sunchip_CX-A99_defconfig
index 7530d7d..3b760d8 100644
--- a/configs/Sunchip_CX-A99_defconfig
+++ b/configs/Sunchip_CX-A99_defconfig
@@ -4,6 +4,7 @@  CONFIG_MACH_SUN9I=y
 CONFIG_DRAM_CLK=600
 CONFIG_DRAM_ZQ=3881915
 CONFIG_DRAM_ODT_EN=y
+CONFIG_SYS_CLK_FREQ=1200000000
 CONFIG_MMC0_CD_PIN="PH17"
 CONFIG_MMC_SUNXI_SLOT_EXTRA=2
 CONFIG_USB0_VBUS_PIN="PH15"
@@ -17,6 +18,7 @@  CONFIG_SPL=y
 # CONFIG_CMD_IMLS is not set
 # CONFIG_CMD_FLASH is not set
 # CONFIG_CMD_FPGA is not set
+CONFIG_AXP_DCDCA_VOLT=1020
 # CONFIG_SPL_DOS_PARTITION is not set
 # CONFIG_SPL_ISO_PARTITION is not set
 # CONFIG_SPL_EFI_PARTITION is not set