[PATCH v2 4/7] sparc32: Do not select ZONE_DMA

From: Sam Ravnborg via B4 Relay
Date: Sat Feb 24 2024 - 12:42:48 EST


From: Sam Ravnborg <sam@xxxxxxxxxxxx>

sparc32 has no limited DMA zone so there is no need to select ZONE_DMA.

Based on analysis from Marciej:
"
Actually I think ZONE_DMA should go too (it's linked to GENERIC_ISA_DMA,
isn't it? -- cf. commit 5ac6da669e24 ("[PATCH] Set CONFIG_ZONE_DMA for
arches with GENERIC_ISA_DMA")), and the whole thing use:

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")

The GENERIC_ISA_DMA option itself was added to arch/sparc/config.in with
2.5.31 as:

define_bool CONFIG_GENERIC_ISA_DMA y

despite of:

define_bool CONFIG_ISA n
"

The sparc32 code did not differ between ZONE_NORMAL and ZONE_DMA,
which confirms the above. This patch drop ZONE_DMA.

Signed-off-by: Sam Ravnborg <sam@xxxxxxxxxxxx>
Reported-by: "Maciej W. Rozycki" <macro@xxxxxxxxxxx>
Cc: Andreas Larsson <andreas@xxxxxxxxxxx>
Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
Cc: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Cc: Maciej W. Rozycki <macro@xxxxxxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
---
arch/sparc/Kconfig | 1 -
arch/sparc/mm/srmmu.c | 1 -
2 files changed, 2 deletions(-)

diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index 734f23daecca..bdbde506c01e 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -62,7 +62,6 @@ config SPARC32
select HAVE_UID16
select LOCK_MM_AND_FIND_VMA
select OLD_SIGACTION
- select ZONE_DMA

config SPARC64
def_bool 64BIT
diff --git a/arch/sparc/mm/srmmu.c b/arch/sparc/mm/srmmu.c
index 852085ada368..7aae2f6f4973 100644
--- a/arch/sparc/mm/srmmu.c
+++ b/arch/sparc/mm/srmmu.c
@@ -975,7 +975,6 @@ void __init srmmu_paging_init(void)
{
unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0 };

- max_zone_pfn[ZONE_DMA] = max_low_pfn;
max_zone_pfn[ZONE_NORMAL] = max_low_pfn;
max_zone_pfn[ZONE_HIGHMEM] = highend_pfn;


--
2.34.1