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authorAkshay Saraswat <akshay.s@samsung.com>2015-02-20 13:27:15 +0530
committerMinkyu Kang <mk7.kang@samsung.com>2015-02-28 18:03:46 +0900
commit67a0652c47ec568ea274f5ff0303c9bba8ceddbf (patch)
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Exynos542x: Add workaround for exynos iROM errata
iROM logic provides undesired jump address for CPU2. This patch adds a programmable susbstitute for a part of iROM logic which wakes up cores and provides jump addresses. This patch creates a logic to make all secondary cores jump to a particular address which evades the possibility of CPU2 jumping to wrong address and create undesired results. Logic of the workaround: Step-1: iROM code checks value at address 0x2020028. Step-2: If value is 0xc9cfcfcf, it jumps to the address (0x202000+CPUid*4), else, it continues executing normally. Step-3: Primary core puts secondary cores in WFE and store 0xc9cfcfcf in 0x2020028 and jump address (pointer to function low_power_start) in (0x202000+CPUid*4). Step-4: When secondary cores recieve event signal they jump to this address and continue execution. Signed-off-by: Kimoon Kim <kimoon.kim@samsung.com> Signed-off-by: Akshay Saraswat <akshay.s@samsung.com> Reviewed-by: Simon Glass <sjg@chromium.org> Tested-by: Simon Glass <sjg@chromium.org> Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
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