| Message ID | 20231016054755.915155-10-hch@lst.de (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Geert Uytterhoeven |
| Headers | show |
| Series | [01/12] riscv: RISCV_NONSTANDARD_CACHE_OPS shouldn't depend on RISCV_DMA_NONCOHERENT | expand |
On Mon, Oct 16, 2023 at 7:48 AM Christoph Hellwig <hch@lst.de> wrote: > Coldfire cores configured without a data cache are DMA coherent and > should thus simply use the simple coherent version of dma-direct. > > Introduce a new COLDFIRE_COHERENT_DMA Kconfig symbol as a convenient > short hand for such configurations, and a M68K_NONCOHERENT_DMA symbol > for all cases where we need to build non-coherent DMA infrastructure > to simplify the Kconfig and code conditionals. > > Not building the non-coherent DMA code slightly reduces the code > size for such configurations. > > Numers for m5249evb_defconfig below: > > text data bss dec hex filename > 2896158 401052 65392 3362602 334f2a vmlinux.before > 2895166 400988 65392 3361546 334b0a vmlinux.after > > Signed-off-by: Christoph Hellwig <hch@lst.de> The m68kclassic-with-MMU parts look fine to me, so Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> I'll defer to Greg for the nommu and Coldfire parts... Gr{oetje,eeting}s, Geert
Hi Christoph, On 16/10/23 15:47, Christoph Hellwig wrote: > Coldfire cores configured without a data cache are DMA coherent and > should thus simply use the simple coherent version of dma-direct. > > Introduce a new COLDFIRE_COHERENT_DMA Kconfig symbol as a convenient > short hand for such configurations, and a M68K_NONCOHERENT_DMA symbol > for all cases where we need to build non-coherent DMA infrastructure > to simplify the Kconfig and code conditionals. > > Not building the non-coherent DMA code slightly reduces the code > size for such configurations. > > Numers for m5249evb_defconfig below: > > text data bss dec hex filename > 2896158 401052 65392 3362602 334f2a vmlinux.before > 2895166 400988 65392 3361546 334b0a vmlinux.after > > Signed-off-by: Christoph Hellwig <hch@lst.de> > --- > arch/m68k/Kconfig | 8 ++++---- > arch/m68k/Kconfig.cpu | 12 ++++++++++++ > arch/m68k/kernel/Makefile | 2 +- > arch/m68k/kernel/dma.c | 2 +- > 4 files changed, 18 insertions(+), 6 deletions(-) > > diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig > index 0430b8ba6b5cc6..6c585eae89f4dc 100644 > --- a/arch/m68k/Kconfig > +++ b/arch/m68k/Kconfig > @@ -3,19 +3,19 @@ config M68K > bool > default y > select ARCH_32BIT_OFF_T > - select ARCH_DMA_ALLOC if !MMU || COLDFIRE > + select ARCH_DMA_ALLOC if M68K_NONCOHERENT_DMA && COLDFIRE > select ARCH_HAS_BINFMT_FLAT > select ARCH_HAS_CPU_FINALIZE_INIT if MMU > select ARCH_HAS_CURRENT_STACK_POINTER > - select ARCH_HAS_DMA_PREP_COHERENT if HAS_DMA && MMU && !COLDFIRE > - select ARCH_HAS_SYNC_DMA_FOR_DEVICE if HAS_DMA > + select ARCH_HAS_DMA_PREP_COHERENT if M68K_NONCOHERENT_DMA && !COLDFIRE > + select ARCH_HAS_SYNC_DMA_FOR_DEVICE if M68K_NONCOHERENT_DMA > select ARCH_HAVE_NMI_SAFE_CMPXCHG if RMW_INSNS > select ARCH_MIGHT_HAVE_PC_PARPORT if ISA > select ARCH_NO_PREEMPT if !COLDFIRE > select ARCH_USE_MEMTEST if MMU_MOTOROLA > select ARCH_WANT_IPC_PARSE_VERSION > select BINFMT_FLAT_ARGVP_ENVP_ON_STACK > - select DMA_DIRECT_REMAP if HAS_DMA && MMU && !COLDFIRE > + select DMA_DIRECT_REMAP if M68K_NONCOHERENT_DMA && !COLDFIRE > select GENERIC_ATOMIC64 > select GENERIC_CPU_DEVICES > select GENERIC_IOMAP > diff --git a/arch/m68k/Kconfig.cpu b/arch/m68k/Kconfig.cpu > index b826e9c677b2ae..e8905d38c714c4 100644 > --- a/arch/m68k/Kconfig.cpu > +++ b/arch/m68k/Kconfig.cpu > @@ -535,3 +535,15 @@ config CACHE_COPYBACK > The ColdFire CPU cache is set into Copy-back mode. > endchoice > endif # HAVE_CACHE_CB > + > +# Coldfire cores that do not have a data cache configured can do coherent DMA. > +config COLDFIRE_COHERENT_DMA > + bool > + default y > + depends on COLDFIRE > + depends on !HAVE_CACHE_CB && !CONFIG_CACHE_D && !CONFIG_CACHE_BOTH ^^^^^^ ^^^^^^ This needs to be "depends on !HAVE_CACHE_CB && !CACHE_D && !CACHE_BOTH". Regards Greg > + > +config M68K_NONCOHERENT_DMA > + bool > + default y > + depends on HAS_DMA && !COLDFIRE_COHERENT_DMA > diff --git a/arch/m68k/kernel/Makefile b/arch/m68k/kernel/Makefile > index af015447dfb4c1..01fb69a5095f43 100644 > --- a/arch/m68k/kernel/Makefile > +++ b/arch/m68k/kernel/Makefile > @@ -23,7 +23,7 @@ obj-$(CONFIG_MMU_MOTOROLA) += ints.o vectors.o > obj-$(CONFIG_MMU_SUN3) += ints.o vectors.o > obj-$(CONFIG_PCI) += pcibios.o > > -obj-$(CONFIG_HAS_DMA) += dma.o > +obj-$(CONFIG_M68K_NONCOHERENT_DMA) += dma.o > > obj-$(CONFIG_KEXEC) += machine_kexec.o relocate_kernel.o > obj-$(CONFIG_BOOTINFO_PROC) += bootinfo_proc.o > diff --git a/arch/m68k/kernel/dma.c b/arch/m68k/kernel/dma.c > index 2e192a5df949bb..f83870cfa79b37 100644 > --- a/arch/m68k/kernel/dma.c > +++ b/arch/m68k/kernel/dma.c > @@ -17,7 +17,7 @@ > > #include <asm/cacheflush.h> > > -#if defined(CONFIG_MMU) && !defined(CONFIG_COLDFIRE) > +#ifndef CONFIG_COLDFIRE > void arch_dma_prep_coherent(struct page *page, size_t size) > { > cache_push(page_to_phys(page), size);
diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig index 0430b8ba6b5cc6..6c585eae89f4dc 100644 --- a/arch/m68k/Kconfig +++ b/arch/m68k/Kconfig @@ -3,19 +3,19 @@ config M68K bool default y select ARCH_32BIT_OFF_T - select ARCH_DMA_ALLOC if !MMU || COLDFIRE + select ARCH_DMA_ALLOC if M68K_NONCOHERENT_DMA && COLDFIRE select ARCH_HAS_BINFMT_FLAT select ARCH_HAS_CPU_FINALIZE_INIT if MMU select ARCH_HAS_CURRENT_STACK_POINTER - select ARCH_HAS_DMA_PREP_COHERENT if HAS_DMA && MMU && !COLDFIRE - select ARCH_HAS_SYNC_DMA_FOR_DEVICE if HAS_DMA + select ARCH_HAS_DMA_PREP_COHERENT if M68K_NONCOHERENT_DMA && !COLDFIRE + select ARCH_HAS_SYNC_DMA_FOR_DEVICE if M68K_NONCOHERENT_DMA select ARCH_HAVE_NMI_SAFE_CMPXCHG if RMW_INSNS select ARCH_MIGHT_HAVE_PC_PARPORT if ISA select ARCH_NO_PREEMPT if !COLDFIRE select ARCH_USE_MEMTEST if MMU_MOTOROLA select ARCH_WANT_IPC_PARSE_VERSION select BINFMT_FLAT_ARGVP_ENVP_ON_STACK - select DMA_DIRECT_REMAP if HAS_DMA && MMU && !COLDFIRE + select DMA_DIRECT_REMAP if M68K_NONCOHERENT_DMA && !COLDFIRE select GENERIC_ATOMIC64 select GENERIC_CPU_DEVICES select GENERIC_IOMAP diff --git a/arch/m68k/Kconfig.cpu b/arch/m68k/Kconfig.cpu index b826e9c677b2ae..e8905d38c714c4 100644 --- a/arch/m68k/Kconfig.cpu +++ b/arch/m68k/Kconfig.cpu @@ -535,3 +535,15 @@ config CACHE_COPYBACK The ColdFire CPU cache is set into Copy-back mode. endchoice endif # HAVE_CACHE_CB + +# Coldfire cores that do not have a data cache configured can do coherent DMA. +config COLDFIRE_COHERENT_DMA + bool + default y + depends on COLDFIRE + depends on !HAVE_CACHE_CB && !CONFIG_CACHE_D && !CONFIG_CACHE_BOTH + +config M68K_NONCOHERENT_DMA + bool + default y + depends on HAS_DMA && !COLDFIRE_COHERENT_DMA diff --git a/arch/m68k/kernel/Makefile b/arch/m68k/kernel/Makefile index af015447dfb4c1..01fb69a5095f43 100644 --- a/arch/m68k/kernel/Makefile +++ b/arch/m68k/kernel/Makefile @@ -23,7 +23,7 @@ obj-$(CONFIG_MMU_MOTOROLA) += ints.o vectors.o obj-$(CONFIG_MMU_SUN3) += ints.o vectors.o obj-$(CONFIG_PCI) += pcibios.o -obj-$(CONFIG_HAS_DMA) += dma.o +obj-$(CONFIG_M68K_NONCOHERENT_DMA) += dma.o obj-$(CONFIG_KEXEC) += machine_kexec.o relocate_kernel.o obj-$(CONFIG_BOOTINFO_PROC) += bootinfo_proc.o diff --git a/arch/m68k/kernel/dma.c b/arch/m68k/kernel/dma.c index 2e192a5df949bb..f83870cfa79b37 100644 --- a/arch/m68k/kernel/dma.c +++ b/arch/m68k/kernel/dma.c @@ -17,7 +17,7 @@ #include <asm/cacheflush.h> -#if defined(CONFIG_MMU) && !defined(CONFIG_COLDFIRE) +#ifndef CONFIG_COLDFIRE void arch_dma_prep_coherent(struct page *page, size_t size) { cache_push(page_to_phys(page), size);
Coldfire cores configured without a data cache are DMA coherent and should thus simply use the simple coherent version of dma-direct. Introduce a new COLDFIRE_COHERENT_DMA Kconfig symbol as a convenient short hand for such configurations, and a M68K_NONCOHERENT_DMA symbol for all cases where we need to build non-coherent DMA infrastructure to simplify the Kconfig and code conditionals. Not building the non-coherent DMA code slightly reduces the code size for such configurations. Numers for m5249evb_defconfig below: text data bss dec hex filename 2896158 401052 65392 3362602 334f2a vmlinux.before 2895166 400988 65392 3361546 334b0a vmlinux.after Signed-off-by: Christoph Hellwig <hch@lst.de> --- arch/m68k/Kconfig | 8 ++++---- arch/m68k/Kconfig.cpu | 12 ++++++++++++ arch/m68k/kernel/Makefile | 2 +- arch/m68k/kernel/dma.c | 2 +- 4 files changed, 18 insertions(+), 6 deletions(-)