unicore32 is a bog standard 32-bit port without larger physical address
space, highmem or any other obvious addressing limitation. There should
be no need to bounce buffer using swiotlb.
Signed-off-by: Christoph Hellwig <[email protected]>
---
Guan, can you double check my assumptions? I really can't find a
reason why unicore32 would need swiotlb.
arch/unicore32/Kconfig | 2 +-
arch/unicore32/include/asm/Kbuild | 1 +
arch/unicore32/include/asm/dma-mapping.h | 22 ----------------------
arch/unicore32/mm/init.c | 3 ---
4 files changed, 2 insertions(+), 26 deletions(-)
delete mode 100644 arch/unicore32/include/asm/dma-mapping.h
diff --git a/arch/unicore32/Kconfig b/arch/unicore32/Kconfig
index 60eae744d8fd..3a3b40f79558 100644
--- a/arch/unicore32/Kconfig
+++ b/arch/unicore32/Kconfig
@@ -4,6 +4,7 @@ config UNICORE32
select ARCH_HAS_DEVMEM_IS_ALLOWED
select ARCH_MIGHT_HAVE_PC_PARPORT
select ARCH_MIGHT_HAVE_PC_SERIO
+ select DMA_DIRECT_OPS
select HAVE_MEMBLOCK
select HAVE_GENERIC_DMA_COHERENT
select HAVE_KERNEL_GZIP
@@ -20,7 +21,6 @@ config UNICORE32
select GENERIC_IOMAP
select MODULES_USE_ELF_REL
select NEED_DMA_MAP_STATE
- select SWIOTLB
help
UniCore-32 is 32-bit Instruction Set Architecture,
including a series of low-power-consumption RISC chip
diff --git a/arch/unicore32/include/asm/Kbuild b/arch/unicore32/include/asm/Kbuild
index bfc7abe77905..1372553dc0a9 100644
--- a/arch/unicore32/include/asm/Kbuild
+++ b/arch/unicore32/include/asm/Kbuild
@@ -4,6 +4,7 @@ generic-y += compat.h
generic-y += current.h
generic-y += device.h
generic-y += div64.h
+generic-y += dma-mapping.h
generic-y += emergency-restart.h
generic-y += exec.h
generic-y += extable.h
diff --git a/arch/unicore32/include/asm/dma-mapping.h b/arch/unicore32/include/asm/dma-mapping.h
deleted file mode 100644
index 790bc2ef4af2..000000000000
--- a/arch/unicore32/include/asm/dma-mapping.h
+++ /dev/null
@@ -1,22 +0,0 @@
-/*
- * linux/arch/unicore32/include/asm/dma-mapping.h
- *
- * Code specific to PKUnity SoC and UniCore ISA
- *
- * Copyright (C) 2001-2010 GUAN Xue-tao
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- */
-#ifndef __UNICORE_DMA_MAPPING_H__
-#define __UNICORE_DMA_MAPPING_H__
-
-#include <linux/swiotlb.h>
-
-static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
-{
- return &swiotlb_dma_ops;
-}
-
-#endif
diff --git a/arch/unicore32/mm/init.c b/arch/unicore32/mm/init.c
index f4950fbfe574..5f72a8d1d953 100644
--- a/arch/unicore32/mm/init.c
+++ b/arch/unicore32/mm/init.c
@@ -234,9 +234,6 @@ void __init bootmem_init(void)
uc32_bootmem_init(min, max_low);
-#ifdef CONFIG_SWIOTLB
- swiotlb_init(1);
-#endif
/*
* Sparsemem tries to allocate bootmem in memory_present(),
* so must be done after the fixed reservations
--
2.19.0
That's right and really good to use direct.c, not swiotlb.c
No special limitation for dma zone in unicore32.
Acked-by: Guan Xuetao <[email protected]>
Thanks,
Guan Xuetao
> -----Original Messages-----
> From: "Christoph Hellwig" <[email protected]>
> Sent Time: 2018-09-27 21:54:34 (Thursday)
> To: "Guan Xuetao" <[email protected]>
> Cc: [email protected], [email protected]
> Subject: [PATCH, RFC] unicore32: remove swiotlb support
>
> unicore32 is a bog standard 32-bit port without larger physical address
> space, highmem or any other obvious addressing limitation. There should
> be no need to bounce buffer using swiotlb.
>
> Signed-off-by: Christoph Hellwig <[email protected]>
> ---
>
> Guan, can you double check my assumptions? I really can't find a
> reason why unicore32 would need swiotlb.
>
> arch/unicore32/Kconfig | 2 +-
> arch/unicore32/include/asm/Kbuild | 1 +
> arch/unicore32/include/asm/dma-mapping.h | 22 ----------------------
> arch/unicore32/mm/init.c | 3 ---
> 4 files changed, 2 insertions(+), 26 deletions(-)
> delete mode 100644 arch/unicore32/include/asm/dma-mapping.h
>
> diff --git a/arch/unicore32/Kconfig b/arch/unicore32/Kconfig
> index 60eae744d8fd..3a3b40f79558 100644
> --- a/arch/unicore32/Kconfig
> +++ b/arch/unicore32/Kconfig
> @@ -4,6 +4,7 @@ config UNICORE32
> select ARCH_HAS_DEVMEM_IS_ALLOWED
> select ARCH_MIGHT_HAVE_PC_PARPORT
> select ARCH_MIGHT_HAVE_PC_SERIO
> + select DMA_DIRECT_OPS
> select HAVE_MEMBLOCK
> select HAVE_GENERIC_DMA_COHERENT
> select HAVE_KERNEL_GZIP
> @@ -20,7 +21,6 @@ config UNICORE32
> select GENERIC_IOMAP
> select MODULES_USE_ELF_REL
> select NEED_DMA_MAP_STATE
> - select SWIOTLB
> help
> UniCore-32 is 32-bit Instruction Set Architecture,
> including a series of low-power-consumption RISC chip
> diff --git a/arch/unicore32/include/asm/Kbuild b/arch/unicore32/include/asm/Kbuild
> index bfc7abe77905..1372553dc0a9 100644
> --- a/arch/unicore32/include/asm/Kbuild
> +++ b/arch/unicore32/include/asm/Kbuild
> @@ -4,6 +4,7 @@ generic-y += compat.h
> generic-y += current.h
> generic-y += device.h
> generic-y += div64.h
> +generic-y += dma-mapping.h
> generic-y += emergency-restart.h
> generic-y += exec.h
> generic-y += extable.h
> diff --git a/arch/unicore32/include/asm/dma-mapping.h b/arch/unicore32/include/asm/dma-mapping.h
> deleted file mode 100644
> index 790bc2ef4af2..000000000000
> --- a/arch/unicore32/include/asm/dma-mapping.h
> +++ /dev/null
> @@ -1,22 +0,0 @@
> -/*
> - * linux/arch/unicore32/include/asm/dma-mapping.h
> - *
> - * Code specific to PKUnity SoC and UniCore ISA
> - *
> - * Copyright (C) 2001-2010 GUAN Xue-tao
> - *
> - * This program is free software; you can redistribute it and/or modify
> - * it under the terms of the GNU General Public License version 2 as
> - * published by the Free Software Foundation.
> - */
> -#ifndef __UNICORE_DMA_MAPPING_H__
> -#define __UNICORE_DMA_MAPPING_H__
> -
> -#include <linux/swiotlb.h>
> -
> -static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
> -{
> - return &swiotlb_dma_ops;
> -}
> -
> -#endif
> diff --git a/arch/unicore32/mm/init.c b/arch/unicore32/mm/init.c
> index f4950fbfe574..5f72a8d1d953 100644
> --- a/arch/unicore32/mm/init.c
> +++ b/arch/unicore32/mm/init.c
> @@ -234,9 +234,6 @@ void __init bootmem_init(void)
>
> uc32_bootmem_init(min, max_low);
>
> -#ifdef CONFIG_SWIOTLB
> - swiotlb_init(1);
> -#endif
> /*
> * Sparsemem tries to allocate bootmem in memory_present(),
> * so must be done after the fixed reservations
> --
> 2.19.0
On Sat, Sep 29, 2018 at 09:40:27PM +0800, Guan Xuetao wrote:
> That's right and really good to use direct.c, not swiotlb.c
> No special limitation for dma zone in unicore32.
Thanks. Added to the dma-mapping tree for 4.20.