Add DMA support for the Coldfire M5441x platform with a global DMA pool
and coherent DMA operations.
Reserve a configurable DRAM pool (default 16MB with CONFIG_DMASIZE) and
initialize it with the dedicated helper.
Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@xxxxxxxxxx>
---
arch/m68k/Kconfig.cpu | 2 ++
arch/m68k/Kconfig.machine | 8 ++++++++
arch/m68k/coldfire/Makefile | 2 ++
arch/m68k/include/asm/dma.h | 1 +
arch/m68k/kernel/dma.c | 10 ++++++++++
arch/m68k/mm/mcfmmu.c | 5 +++++
6 files changed, 28 insertions(+)
diff --git a/arch/m68k/Kconfig.cpu b/arch/m68k/Kconfig.cpu
index c9a7e602d8a4da8e5094762e90c7b1a1ab1acfdf..66e5f62a0eb280f6029e7501f4fa152f422b76b4 100644
--- a/arch/m68k/Kconfig.cpu
+++ b/arch/m68k/Kconfig.cpu
@@ -303,6 +303,8 @@ config M5441x
select COLDFIRE_PIT_TIMER
select MMU_COLDFIRE if MMU
select HAVE_CACHE_CB
+ select DMA_GLOBAL_POOL
+ select ARCH_HAS_DMA_OPS
help
Freescale Coldfire 54410/54415/54416/54417/54418 processor support.
diff --git a/arch/m68k/Kconfig.machine b/arch/m68k/Kconfig.machine
index de39f23b180ee21d3d3a028ad46f815f3690b1ad..1467d1ff349bb26714a3c99f593a2a71c9ad273d 100644
--- a/arch/m68k/Kconfig.machine
+++ b/arch/m68k/Kconfig.machine
@@ -405,6 +405,14 @@ config KERNELBASE
a system with the RAM based at address 0, and leaving enough room
for the theoretical maximum number of 256 vectors.
+config DMASIZE
+ hex "Size of DRAM (in bytes) reserved pool"
+ default "0x1000000"
+ depends on DMA_GLOBAL_POOL
+ help
+ Define the DMA pool size, allocated at init time, which can then
+ be used by DMA engine. Defaults to 16MB.
+
comment "ROM configuration"
config ROM
diff --git a/arch/m68k/coldfire/Makefile b/arch/m68k/coldfire/Makefile
index c56bc0dc7f2e338c8275cfd15656f80e78825254..b30c55ec722401822651cb329a9910cfc2d1d788 100644
--- a/arch/m68k/coldfire/Makefile
+++ b/arch/m68k/coldfire/Makefile
@@ -31,6 +31,8 @@ obj-$(CONFIG_M5407) += m5407.o intc.o reset.o
obj-$(CONFIG_M54xx) += m54xx.o intc-2.o
obj-$(CONFIG_M5441x) += m5441x.o intc-simr.o reset.o
+obj-$(CONFIG_ARCH_HAS_DMA_OPS) += dma_ops.o
+
obj-$(CONFIG_COLDFIRE_PIT_TIMER) += pit.o
obj-$(CONFIG_COLDFIRE_TIMERS) += timers.o
obj-$(CONFIG_COLDFIRE_SLTIMERS) += sltimers.o
diff --git a/arch/m68k/include/asm/dma.h b/arch/m68k/include/asm/dma.h
index 1c8d9c5bc2fadeb425965974bdfb497577ebcc3b..53f9c1570ce62ddaa521d85d9ef64523e8ad0919 100644
--- a/arch/m68k/include/asm/dma.h
+++ b/arch/m68k/include/asm/dma.h
@@ -6,4 +6,5 @@
bootmem allocator (but this should do it for this) */
#define MAX_DMA_ADDRESS PAGE_OFFSET
+extern size_t dma_coldfire_base;
#endif /* _M68K_DMA_H */
diff --git a/arch/m68k/kernel/dma.c b/arch/m68k/kernel/dma.c
index 16063783aa80c6ef200567543f98f011a2ac4dd2..bc66b012de79be842b55f3d82726a00c929416b9 100644
--- a/arch/m68k/kernel/dma.c
+++ b/arch/m68k/kernel/dma.c
@@ -43,3 +43,13 @@ void arch_sync_dma_for_device(phys_addr_t handle, size_t size,
break;
}
}
+
+#ifdef CONFIG_DMA_GLOBAL_POOL
+static int __init coldfire_dma_init(void)
+{
+ return dma_init_global_coherent(PFN_PHYS(PFN_DOWN(coldfire_dma_base)),
+ CONFIG_DMASIZE);
+}
+
+core_initcall(coldfire_dma_init);
+#endif
diff --git a/arch/m68k/mm/mcfmmu.c b/arch/m68k/mm/mcfmmu.c
index 9a6fa342e872e32ca9566ebfe247531c808f49d6..f6c560ea17a68ff6546b0683461b6b9ffb587db7 100644
--- a/arch/m68k/mm/mcfmmu.c
+++ b/arch/m68k/mm/mcfmmu.c
@@ -156,6 +156,8 @@ int cf_tlb_miss(struct pt_regs *regs, int write, int dtlb, int extension_word)
return ret;
}
+size_t coldfire_dma_base = _ramend - CONFIG_DMASIZE;
+
void __init cf_bootmem_alloc(void)
{
unsigned long memstart;
@@ -179,6 +181,9 @@ void __init cf_bootmem_alloc(void)
/* Reserve kernel text/data/bss */
memblock_reserve(_rambase, memstart - _rambase);
+ /* Reserve DMA */
+ memblock_reserve(coldfire_dma_base, CONFIG_DMASIZE);
+
m68k_virt_to_node_shift = fls(_ramend - 1) - 6;
module_fixup(NULL, __start_fixup, __stop_fixup);
--
2.39.5
