u-boot/arch/arm/cpu
Siarhei Siamashka f257796773 sunxi: dram: Remove broken super-standby remnants
If the dram->ppwrsctl (SDR_DPCR) register has the lowest bit set to 1,
this means that DRAM is currently in self-refresh mode and retaining the
old data. Since we have no idea what to do in this situation yet, just
set this register to 0 and initialize DRAM in the same way as on any
normal reboot (discarding whatever was stored there).

This part of code was apparently used by the Allwinner boot0 bootloader
to handle resume from the so-called super-standby mode. But this
particular code got somehow mangled on the way from the boot0 bootloader
to the u-boot-sunxi bootloader and has no chance of doing anything even
remotely sane. For example:
1. in the original boot0 code we had "mctl_write_w(SDR_DPCR,
   0x16510000)" (write to the register) and in the u-boot it now looks
   like "setbits_le32(&dram->ppwrsctl, 0x16510000)" (set bits in the
   register)
2. in the original boot0 code it was issuing three commands "0x12, 0x17,
   0x13" (Self-Refresh entry, Self-Refresh exit, Refresh), but in the
   u-boot they have become "0x12, 0x12, 0x13" (Self-Refresh entry,
   Self-Refresh entry, Refresh)

Signed-off-by: Siarhei Siamashka <siarhei.siamashka@gmail.com>
Acked-by: Ian Campbell <ijc@hellion.org.uk>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
2014-08-12 08:42:32 +02:00
..
arm720t spl: consolidate arch/arm/include/asm/arch-*/spl.h 2014-06-06 10:05:34 +02:00
arm920t arm: ep9315: Return back Cirrus Logic EDB9315A board support 2014-07-04 23:45:48 +02:00
arm926ejs ARM: kirkwood: add mvsdio driver 2014-08-01 18:44:56 +03:00
arm946es arm: move exception handling out of start.S files 2014-05-15 16:24:53 +02:00
arm1136 arm: move exception handling out of start.S files 2014-05-15 16:24:53 +02:00
arm1176 arm: move exception handling out of start.S files 2014-05-15 16:24:53 +02:00
arm_intcm arm: move exception handling out of start.S files 2014-05-15 16:24:53 +02:00
armv7 sunxi: dram: Remove broken super-standby remnants 2014-08-12 08:42:32 +02:00
armv8 ARMv8/ls2085a_emu: Add LS2085A emulator and simulator board support 2014-07-04 19:48:41 +02:00
at91-common ARM: atmel: switch to main crystal osc for SPL boot 2014-05-27 00:10:40 +02:00
pxa arm: move exception handling out of start.S files 2014-05-15 16:24:53 +02:00
sa1100 arm: move exception handling out of start.S files 2014-05-15 16:24:53 +02:00
tegra-common ARM: tegra: add function to enable input clamping on tristate 2014-05-13 10:41:31 -07:00
tegra20-common Merge branch 'u-boot/master' 2014-05-09 11:50:14 +02:00
tegra30-common ARM: tegra: Tegra30 pinmux cleanup 2014-04-17 08:41:05 -07:00
tegra114-common ARM: tegra: Tegra114 pinmux cleanup 2014-04-17 08:41:06 -07:00
tegra124-common ARM: tegra: Tegra124 pinmux cleanup 2014-04-17 08:41:06 -07:00
Makefile kbuild: use boolean macros to select tegra*-common directory 2014-04-17 17:44:35 -04:00
u-boot-spl.lds arm: move exception handling out of start.S files 2014-05-15 16:24:53 +02:00
u-boot.lds ARM: HYP/non-sec: add separate section for secure code 2014-07-28 17:07:23 +02:00