[PATCH v2 1/4] ARM: ep93xx: switch to SPARSEMEM
Florian Fainelli
f.fainelli at gmail.com
Sun Sep 3 10:43:44 PDT 2017
From: H Hartley Sweeten <hsweeten at visionengravers.com>
The EP93xx has four chip selects that can be used for the SDRAM memory.
These chip selects are decoded to specify an address domain:
SDCS3 0x00000000-0x0fffffff with Boot Option ASDO=1
SDCS0 0xc0000000-0xcfffffff
SDCS1 0xd0000000-0xdfffffff
SDCS2 0xe0000000-x0efffffff
SDCS3 0xf0000000-0xffffffff with Boot Option ASDO=0
Because of the row/column/bank architecture of SDRAM, the mapping of
these memories into the processor's memory space is discontiguous.
Most ep93xx systems only use one of the chip selects. For these systems,
ARCH_HAS_HOLES_MEMORYMODEL has worked fine to handle the discontiguous
memory.
But, some of the TS-72xx boards use multiple chip selects. The TS-7300 in
particular uses SDCS3 (with ASDO=1) and SDCS2. On that system with
ARCH_HAS_HOLES_MEMORYMODEL the SDCS2 memory does not get handled correctly
and results in the system not booting.
Change the EP93xx to ARCH_SPARSEMEM_ENABLE. This handles the discontiguous
memory for all configurations.
This has been tested on the following ep93xx platforms:
EDB9307A with 64 MiB on SDCS0
Vision EP9307 with 64 MiB on SDCS0
TS-7300 with 64 MiB on SDCS3 (with ASDO=1) and 64 MiB on SDCS2
sim.one with 64 MiB on SDCS0
Signed-off-by: H Hartley Sweeten <hsweeten at visionengravers.com>
Tested-by: Linus Walleij <linus.walleij at linaro.org>
Cc: Russell King <linux at armlinux.org.uk>
---
arch/arm/Kconfig | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index a208bfe367b5..87a6b09067c2 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -378,7 +378,7 @@ config ARCH_EBSA110
config ARCH_EP93XX
bool "EP93xx-based"
- select ARCH_HAS_HOLES_MEMORYMODEL
+ select ARCH_SPARSEMEM_ENABLE
select ARM_AMBA
select ARM_PATCH_PHYS_VIRT
select ARM_VIC
--
2.11.0
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