[RFC PATCH 02/17] powerpc: Split up PHYS_64BIT config option to fix "select" issues

From: Kyle Moffett
Date: Wed Nov 09 2011 - 19:08:17 EST

The "CONFIG_PHYS_64BIT" option violates the Kconfig best-practices in
various colorful ways. It has explicit dependencies, but it is also
"select"ed by various CPUs and platforms. It is not set on 64-bit
systems, but it is used by a number of pieces of powerpc code to enable
or disable 64-bit physical address support.

To resolve these issues, the option has now been split into 3:

CONFIG_PHYS_64BIT_SUPPORTED:
This hidden option should be selected by any CPU type which supports
64-bit physical addresses. This will enable the PHYS_64BIT option
to be selected. It is (obviously) always set on PPC64.

CONFIG_PHYS_64BIT_DT_REQUIRED:
This hidden option should be selected by any board or platform which
has >32-bit physical devices present in hardware. If this is set
then the CONFIG_PHYS_64BIT option will be forcibly enabled and
hidden from the user. It is (obviously) always set on PPC64.

CONFIG_PHYS_64BIT:
This option is user-controllable, where allowed by CPU and platform
settings, and should never be pointed at with a "select" statement.
Due to the values of the above two options, this is never visible on
PPC64.

Signed-off-by: Kyle Moffett <Kyle.D.Moffett@xxxxxxxxxx>
---
arch/powerpc/Kconfig | 4 ++--
arch/powerpc/platforms/82xx/Kconfig | 2 +-
arch/powerpc/platforms/83xx/Kconfig | 2 +-
arch/powerpc/platforms/85xx/Kconfig | 12 ++++++------
arch/powerpc/platforms/86xx/Kconfig | 1 +
arch/powerpc/platforms/Kconfig.cputype | 25 ++++++++++++++++++-------
6 files changed, 29 insertions(+), 17 deletions(-)

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index b177caa..27e31c5 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -18,10 +18,10 @@ config WORD_SIZE
default 32 if !PPC64

config ARCH_PHYS_ADDR_T_64BIT
- def_bool PPC64 || PHYS_64BIT
+ def_bool PHYS_64BIT

config ARCH_DMA_ADDR_T_64BIT
- def_bool ARCH_PHYS_ADDR_T_64BIT
+ def_bool PHYS_64BIT

config MMU
bool
diff --git a/arch/powerpc/platforms/82xx/Kconfig b/arch/powerpc/platforms/82xx/Kconfig
index 7c7df40..849d403 100644
--- a/arch/powerpc/platforms/82xx/Kconfig
+++ b/arch/powerpc/platforms/82xx/Kconfig
@@ -1,6 +1,6 @@
menuconfig PPC_82xx
bool "82xx-based boards (PQ II)"
- depends on 6xx
+ depends on 6xx && !PHYS_64BIT

if PPC_82xx

diff --git a/arch/powerpc/platforms/83xx/Kconfig b/arch/powerpc/platforms/83xx/Kconfig
index 670a033..1ed8877 100644
--- a/arch/powerpc/platforms/83xx/Kconfig
+++ b/arch/powerpc/platforms/83xx/Kconfig
@@ -1,6 +1,6 @@
menuconfig PPC_83xx
bool "83xx-based boards"
- depends on 6xx
+ depends on 6xx && !PHYS_64BIT
select PPC_UDBG_16550
select PPC_PCI_CHOICE
select FSL_PCI if PCI
diff --git a/arch/powerpc/platforms/85xx/Kconfig b/arch/powerpc/platforms/85xx/Kconfig
index 9088381..37f9de7 100644
--- a/arch/powerpc/platforms/85xx/Kconfig
+++ b/arch/powerpc/platforms/85xx/Kconfig
@@ -80,7 +80,7 @@ config P1010_RDB
config P1022_DS
bool "Freescale P1022 DS"
select DEFAULT_UIMAGE
- select PHYS_64BIT # The DTS has 36-bit addresses
+ select PHYS_64BIT_DT_REQUIRED # The DTS has 36-bit addresses
select SWIOTLB
help
This option enables support for the Freescale P1022DS reference board.
@@ -175,7 +175,7 @@ config P2041_RDB
bool "Freescale P2041 RDB"
select DEFAULT_UIMAGE
select PPC_E500MC
- select PHYS_64BIT
+ select PHYS_64BIT_DT_REQUIRED
select SWIOTLB
select ARCH_REQUIRE_GPIOLIB
select GPIO_MPC8XXX
@@ -189,7 +189,7 @@ config P3041_DS
bool "Freescale P3041 DS"
select DEFAULT_UIMAGE
select PPC_E500MC
- select PHYS_64BIT
+ select PHYS_64BIT_DT_REQUIRED
select SWIOTLB
select ARCH_REQUIRE_GPIOLIB
select GPIO_MPC8XXX
@@ -203,7 +203,7 @@ config P3060_QDS
bool "Freescale P3060 QDS"
select DEFAULT_UIMAGE
select PPC_E500MC
- select PHYS_64BIT
+ select PHYS_64BIT_DT_REQUIRED
select SWIOTLB
select MPC8xxx_GPIO
select HAS_RAPIDIO
@@ -216,7 +216,7 @@ config P4080_DS
bool "Freescale P4080 DS"
select DEFAULT_UIMAGE
select PPC_E500MC
- select PHYS_64BIT
+ select PHYS_64BIT_DT_REQUIRED
select SWIOTLB
select ARCH_REQUIRE_GPIOLIB
select GPIO_MPC8XXX
@@ -233,7 +233,7 @@ config P5020_DS
select DEFAULT_UIMAGE
select E500
select PPC_E500MC
- select PHYS_64BIT
+ select PHYS_64BIT_DT_REQUIRED
select SWIOTLB
select ARCH_REQUIRE_GPIOLIB
select GPIO_MPC8XXX
diff --git a/arch/powerpc/platforms/86xx/Kconfig b/arch/powerpc/platforms/86xx/Kconfig
index 8d6599d..576eb43 100644
--- a/arch/powerpc/platforms/86xx/Kconfig
+++ b/arch/powerpc/platforms/86xx/Kconfig
@@ -5,6 +5,7 @@ menuconfig PPC_86xx
select FSL_SOC
select ALTIVEC
select ARCH_WANT_OPTIONAL_GPIOLIB
+ select PHYS_64BIT_SUPPORTED
help
The Freescale E600 SoCs have 74xx cores.

diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
index 9210e94..0ab01b0 100644
--- a/arch/powerpc/platforms/Kconfig.cputype
+++ b/arch/powerpc/platforms/Kconfig.cputype
@@ -26,6 +26,7 @@ config PPC_BOOK3S_32

config PPC_85xx
bool "Freescale 85xx"
+ select PHYS_64BIT_SUPPORTED
select E500

config PPC_8xx
@@ -47,7 +48,8 @@ config 44x
select PPC_UDBG_16550
select 4xx_SOC
select PPC_PCI_CHOICE
- select PHYS_64BIT
+ select PHYS_64BIT_SUPPORTED
+ select PHYS_64BIT_DT_REQUIRED

config E200
bool "Freescale e200"
@@ -187,14 +189,20 @@ config PPC_FSL_BOOK3E
select PPC_SMP_MUXED_IPI
default y if FSL_BOOKE

-config PTE_64BIT
- bool
- depends on 44x || E500 || PPC_86xx
- default y if PHYS_64BIT
+## Only some 32-bit CPUs support 64-bit physical addresses
+config PHYS_64BIT_SUPPORTED
+ def_bool PPC64
+
+## Some 32-bit system device trees have >32-bit physical addresses, and so
+## the kernel won't boot unless those are supported.
+config PHYS_64BIT_DT_REQUIRED
+ def_bool PPC64

+## DO NOT "select" this user-visible symbol, select the two above instead!
config PHYS_64BIT
- bool 'Large physical address support' if E500 || PPC_86xx
- depends on (44x || E500 || PPC_86xx) && !PPC_83xx && !PPC_82xx
+ def_bool PHYS_64BIT_DT_REQUIRED
+ prompt 'Large physical address support' if !PHYS_64BIT_DT_REQUIRED
+ depends on PHYS_64BIT_SUPPORTED
---help---
This option enables kernel support for larger than 32-bit physical
addresses. This feature may not be available on all cores.
@@ -205,6 +213,9 @@ config PHYS_64BIT

If in doubt, say N here.

+config PTE_64BIT
+ def_bool PHYS_64BIT
+
config ALTIVEC
bool "AltiVec Support"
depends on 6xx || POWER4
--
1.7.2.5

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