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5 commits

Author SHA1 Message Date
Masahiro Yamada
36223f5de8 ARM: uniphier: add work-around to support Micro Support Card v3.6.10
Due to some hardware guy's awful work, this version is not compatible
with v3.6: the logic of BIT(0) of the reset logic is inverted! (and
v3.6.10 is horribly wrong in multiple ways), but this is what we have
to solve now.

The v3.6 expects 0x0000 set to the register for reset de-assertion,
while v3.6 does 0x0001.

This commit (ab)uses another bug of v3.6.10 to work around the issue.
The UniPhier System Bus is a 16-bit bus, which this support card is
connected to.  A 32-bit write to the bus (writel() function call) is
divided into two 16-bit write transactions, with LSB the first.  What
is amazing for v3.6.10 is that access to address 4N + 2 goes to 4N
(Jesus Christ!).

For clarification, things are like this:

    writel(0x00010000, MICRO_SUPPORT_CARD_RESET);

is done with two bus transactions as follows

    [1] write 0x0000 to address MICRO_SUPPORT_CARD
    [2] write 0x0001 to address MICRO_SUPPORT_CARD + 2

For v3.6, [1] is written to the register and [2] is correctly ignored
because there is nothing at the address MICRO_SUPPORT_CARD + 2.  This
is what we expect.

For v3.6.10, [1] is written to the reset register and then [2] is
over-written to the same register due to the bus access bug.

For the latter, it produces a glitch signal to the BIT[0], so the
device state is lost due to the reset pulse.  This solution only
works for the start-up code.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2016-03-24 01:45:19 +09:00
Masahiro Yamada
11d3ede42c ARM: uniphier: fix warnings reported by aarch64 compiler
The UniPhier SoC family has not supported ARMv8 yet, but these would
cause warnings if they were compiled with a 64bit compiler.  Before
adding the ARMv8 support really, fix them now.

Because UniPhier SoCs do not support Large Physical Address Extension,
casting "phys_addr_t" into "unsigned long" would carry the address
as is.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2016-03-01 00:33:29 +09:00
Masahiro Yamada
107b3fb484 ARM: uniphier: move headers out of include/mach directory
These headers are only included locally in arch/arm/mach-uniphier/.
There is no reason to export them by putting in the mach/ directory.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2016-01-13 01:54:53 +09:00
Masahiro Yamada
9475f8de88 ARM: uniphier: kill bogus header includes
These includes are not necessary.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2016-01-13 01:54:38 +09:00
Masahiro Yamada
d7728aa408 ARM: uniphier: move CONFIG_SUPPORT_CARD_* macros to local file
It is no longer necessary to define CONFIG_SUPPORT_CARD_* globally.
Move them to a C file as local macros.  Also, rename the C file.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2015-09-25 00:27:53 +09:00
Renamed from arch/arm/mach-uniphier/support_card.c (Browse further)