The attached patches slow-down the DDR's clock (from 528000000Hz to 396000000Hz) on i.MX6Q Sabre SDB-P boards. These were tested on Android JB4.2.2_1.0.0 and Linux L3.0.35_4.1.0.
To verify patches were correctly applied, one the serial console one should see the following TWO bold lines
Board: i.MX6Q-SABRESD: unknown-board Board: 0x63012 [POR ]
Boot Device: MMC
I2C: ready
DRAM: 1 GB
MMC: FSL_USDHC: 0,FSL_USDHC: 1,FSL_USDHC: 2,FSL_USDHC: 3
*** Warning - bad CRC or MMC, using default environment
mx6q pll1: 792MHz
mx6q pll2: 528MHz
mx6q pll3: 480MHz
mx6q pll8: 50MHz
ipg clock : 49500000Hz
ipg per clock : 49500000Hz
uart clock : 80000000Hz
cspi clock : 60000000Hz
ahb clock : 99000000Hz
axi clock : 198000000Hz
emi_slow clock: 99000000Hz
ddr clock : 396000000Hz
usdhc1 clock : 198000000Hz
usdhc2 clock : 198000000Hz
usdhc3 clock : 198000000Hz
usdhc4 clock : 198000000Hz
nfc clock : 24000000Hz
In: serial
Out: serial
Err: serial
Found PFUZE100! deviceid=10,revid=10
Net: got MAC address from IIM: 00:04:9f:02:67:46
FEC0 [PRIME]
Hit any key to stop autoboot: 0
kernel @ 10808000 (4709060)
ramdisk @ 11800000 (183100)
kernel cmdline:
use boot.img command line:
console=ttymxc0,115200 init=/init video=mxcfb0:dev=ldb,bpp=32 video=mxcfb1:off video=mxcfb2:off fbmem=10M fb0base=0x27b00000 vmalloc=400M androidboot.console=ttymxc0 androidboot.hardware=freescale
Starting kernel ...
Uncompressing Linux... done, booting the kernel.
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sched_clock: 32 bits at 3000kHz, resolution 333ns, wraps every 1431655ms
Set periph_clk's parent to pll2_pfd_400!
arm_max_freq=1.2GHz
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