Guys,
I've been looking at converting 32-bit powerpc's DMA code over to the
64-bit method, where there is a dma_ops structure inside archdata
that tells us which operations a device should use for DMA. I'll be
needing this shortly because I need to implement swiotlb to deal with
PCI and large amounts of RAM on 32-bit systems that support 36-bit
physical addressing. (Yes, I know. Fun for me. Woohoo.)
Anyway, I have an initial booting first pass, and wanted to get some
feedback. What I've done at this point is to make dma_64 common to both
architectures (will rename it when I send a real patch...). The
dma_direct_* functions have been changed to work on both 32/64, and the
old dma_* functionality in dma-mapping.h has been removed. For now, to
avoid whacking on every 32-bit platform, the get_dma_ops() function has
been changed to return &dma_direct_ops if the device pointer exists but
the dma_ops field is NULL. I'm not sure if this needs to be ifdef'd for
64-bit?
I've copied a bit of code over from pci_64.c into pci_common.c - some of
it isn't in use yet but will be once I start doing actual setup in the
platform code. pcibios_setup_new_device() becomes common as well. I've
also temporarily hacked the 32-bit code to set archdata.dma_data to
PCI_DRAM_OFFSET, so we can eliminate the use of virt_to_bus() and instead
use the 64-bit method, which gets rid of some ugly ifdefs in the dma code.
That's really about it - the preliminary patch is below - clearly it will
need some cleanup, but I wanted to post early and often. Any feedback or
suggestions on cleaning this up are greatly appreciated.
Thanks!
-Becky
-----------
diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
index ebf8d16..34a6a82 100644
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -55,10 +55,10 @@ extra-$(CONFIG_8xx) := head_8xx.o
extra-y += vmlinux.lds
obj-y += time.o prom.o traps.o setup-common.o \
- udbg.o misc.o io.o \
+ udbg.o misc.o io.o dma_64.o\
misc_$(CONFIG_WORD_SIZE).o
obj-$(CONFIG_PPC32) += entry_32.o setup_32.o
-obj-$(CONFIG_PPC64) += dma_64.o iommu.o
+obj-$(CONFIG_PPC64) += iommu.o
obj-$(CONFIG_PPC_MULTIPLATFORM) += prom_init.o
obj-$(CONFIG_MODULES) += ppc_ksyms.o
obj-$(CONFIG_BOOTX_TEXT) += btext.o
diff --git a/arch/powerpc/kernel/dma.c b/arch/powerpc/kernel/dma_64.c
index 8423907..0199a3b 100644
--- a/arch/powerpc/kernel/dma_64.c
+++ b/arch/powerpc/kernel/dma_64.c
@@ -8,9 +8,11 @@
#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <asm/bug.h>
-#include <asm/iommu.h>
#include <asm/abs_addr.h>
+#ifdef CONFIG_PPC64
+#include <asm/iommu.h>
+
/*
* Generic iommu implementation
*/
@@ -108,6 +110,8 @@ struct dma_mapping_ops dma_iommu_ops = {
.dma_supported = dma_iommu_dma_supported,
};
EXPORT_SYMBOL(dma_iommu_ops);
+#endif /* CONFIG_PPC64 */
+
/*
* Generic direct DMA implementation
@@ -126,14 +130,28 @@ static unsigned long get_dma_direct_offset(struct device
*dev)
static void *dma_direct_alloc_coherent(struct device *dev, size_t size,
dma_addr_t *dma_handle, gfp_t flag)
{
- struct page *page;
void *ret;
+
+#ifdef CONFIG_PPC64
+ struct page *page;
int node = dev->archdata.numa_node;
page = alloc_pages_node(node, flag, get_order(size));
if (page == NULL)
return NULL;
ret = page_address(page);
+#else
+ /* ignore region specifiers */
+ flag &= ~(__GFP_DMA | __GFP_HIGHMEM);
+
+ if (dev == NULL || dev->coherent_dma_mask < 0xffffffff)
+ flag |= GFP_DMA;
+
+ ret = (void *)__get_free_pages(flag, get_order(size));
+ if (ret == NULL)
+ return NULL;
+#endif
+
memset(ret, 0, size);
*dma_handle = virt_to_abs(ret) + get_dma_direct_offset(dev);
@@ -146,10 +164,29 @@ static void dma_direct_free_coherent(struct device *dev,
size_t size,
free_pages((unsigned long)vaddr, get_order(size));
}
+/*
+ * Version of dma_direct_[alloc/free]_coherent for non-coherent devices or
+ * processors.
+ */
+#ifdef CONFIG_NOT_COHERENT_CACHE
+static void *dma_direct_alloc_noncoherent(struct device *dev, size_t size,
+ dma_addr_t *dma_handle, gfp_t flag)
+{
+ return __dma_alloc_coherent(size, dma_handle, flag);
+}
+
+static void dma_direct_free_noncoherent(struct device *dev, size_t size,
+ void *vaddr, dma_addr_t dma_handle)
+{
+ __dma_free_coherent(size, vaddr);
+}
+#endif
+
static dma_addr_t dma_direct_map_single(struct device *dev, void *ptr,
size_t size,
enum dma_data_direction direction)
{
+ __dma_sync(ptr, size, direction);
return virt_to_abs(ptr) + get_dma_direct_offset(dev);
}
@@ -180,16 +217,25 @@ static void dma_direct_unmap_sg(struct device *dev,
struct scatterlist *sg,
static int dma_direct_dma_supported(struct device *dev, u64 mask)
{
+#ifdef CONFIG_PPC64
/* Could be improved to check for memory though it better be
* done via some global so platforms can set the limit in case
* they have limited DMA windows
*/
return mask >= DMA_32BIT_MASK;
+#else
+ return 1;
+#endif
}
struct dma_mapping_ops dma_direct_ops = {
+#ifdef CONFIG_NOT_COHERENT_CACHE
+ .alloc_coherent = dma_direct_alloc_noncoherent,
+ .free_coherent = dma_direct_free_noncoherent,
+#else
.alloc_coherent = dma_direct_alloc_coherent,
.free_coherent = dma_direct_free_coherent,
+#endif
.map_single = dma_direct_map_single,
.unmap_single = dma_direct_unmap_single,
.map_sg = dma_direct_map_sg,
diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c
index 980fe32..35d5b87 100644
--- a/arch/powerpc/kernel/pci-common.c
+++ b/arch/powerpc/kernel/pci-common.c
@@ -56,6 +56,34 @@ resource_size_t isa_mem_base;
/* Default PCI flags is 0 */
unsigned int ppc_pci_flags;
+static struct dma_mapping_ops *pci_dma_ops;
+
+void set_pci_dma_ops(struct dma_mapping_ops *dma_ops)
+{
+ pci_dma_ops = dma_ops;
+}
+
+struct dma_mapping_ops *get_pci_dma_ops(void)
+{
+ return pci_dma_ops;
+}
+EXPORT_SYMBOL(get_pci_dma_ops);
+
+int pci_set_dma_mask(struct pci_dev *dev, u64 mask)
+{
+ return dma_set_mask(&dev->dev, mask);
+}
+
+int pci_set_consistent_dma_mask(struct pci_dev *dev, u64 mask)
+{
+ int rc;
+
+ rc = dma_set_mask(&dev->dev, mask);
+ dev->dev.coherent_dma_mask = dev->dma_mask;
+
+ return rc;
+}
+
struct pci_controller *pcibios_alloc_controller(struct device_node *dev)
{
struct pci_controller *phb;
@@ -180,6 +208,36 @@ char __devinit *pcibios_setup(char *str)
return str;
}
+void __devinit pcibios_setup_new_device(struct pci_dev *dev)
+{
+ struct dev_archdata *sd = &dev->dev.archdata;
+
+ sd->of_node = pci_device_to_OF_node(dev);
+
+ DBG("PCI: device %s OF node: %s\n", pci_name(dev),
+ sd->of_node ? sd->of_node->full_name : "<none>");
+
+ sd->dma_ops = pci_dma_ops;
+#ifdef CONFIG_PPC32
+ /* Hack for now until the platforms do setup correctly.
+ * This value is *only* good in the generic dma_direct code,
+ * setting of this needs to be done by plat code based on which
+ * set of dma_ops it has. Since we only currently use
+ * dma_direct_ops on ppc32, this works for now.
+ */
+ sd->dma_data = (void *)PCI_DRAM_OFFSET;
+#endif
+
+#ifdef CONFIG_NUMA
+ sd->numa_node = pcibus_to_node(dev->bus);
+#else
+ sd->numa_node = -1;
+#endif
+ if (ppc_md.pci_dma_dev_setup)
+ ppc_md.pci_dma_dev_setup(dev);
+}
+EXPORT_SYMBOL(pcibios_setup_new_device);
+
/*
* Reads the interrupt pin to determine if interrupt is use by card.
* If the interrupt is used, then gets the interrupt line from the
diff --git a/arch/powerpc/kernel/pci_32.c b/arch/powerpc/kernel/pci_32.c
index 88db4ff..174b77e 100644
--- a/arch/powerpc/kernel/pci_32.c
+++ b/arch/powerpc/kernel/pci_32.c
@@ -424,6 +424,7 @@ void __devinit pcibios_do_bus_setup(struct pci_bus *bus)
unsigned long io_offset;
struct resource *res;
int i;
+ struct pci_dev *dev;
/* Hookup PHB resources */
io_offset = (unsigned long)hose->io_base_virt - isa_io_base;
@@ -457,6 +458,12 @@ void __devinit pcibios_do_bus_setup(struct pci_bus *bus)
bus->resource[i+1] = res;
}
}
+
+ if (ppc_md.pci_dma_bus_setup)
+ ppc_md.pci_dma_bus_setup(bus);
+
+ list_for_each_entry(dev, &bus->devices, bus_list)
+ pcibios_setup_new_device(dev);
}
/* the next one is stolen from the alpha port... */
diff --git a/arch/powerpc/kernel/pci_64.c b/arch/powerpc/kernel/pci_64.c
index 5275074..2a5487c 100644
--- a/arch/powerpc/kernel/pci_64.c
+++ b/arch/powerpc/kernel/pci_64.c
@@ -52,35 +52,6 @@ EXPORT_SYMBOL(pci_io_base);
LIST_HEAD(hose_list);
-static struct dma_mapping_ops *pci_dma_ops;
-
-void set_pci_dma_ops(struct dma_mapping_ops *dma_ops)
-{
- pci_dma_ops = dma_ops;
-}
-
-struct dma_mapping_ops *get_pci_dma_ops(void)
-{
- return pci_dma_ops;
-}
-EXPORT_SYMBOL(get_pci_dma_ops);
-
-
-int pci_set_dma_mask(struct pci_dev *dev, u64 mask)
-{
- return dma_set_mask(&dev->dev, mask);
-}
-
-int pci_set_consistent_dma_mask(struct pci_dev *dev, u64 mask)
-{
- int rc;
-
- rc = dma_set_mask(&dev->dev, mask);
- dev->dev.coherent_dma_mask = dev->dma_mask;
-
- return rc;
-}
-
static void fixup_broken_pcnet32(struct pci_dev* dev)
{
if ((dev->class>>8 == PCI_CLASS_NETWORK_ETHERNET)) {
@@ -548,26 +519,6 @@ int __devinit pcibios_map_io_space(struct pci_bus *bus)
}
EXPORT_SYMBOL_GPL(pcibios_map_io_space);
-void __devinit pcibios_setup_new_device(struct pci_dev *dev)
-{
- struct dev_archdata *sd = &dev->dev.archdata;
-
- sd->of_node = pci_device_to_OF_node(dev);
-
- DBG("PCI: device %s OF node: %s\n", pci_name(dev),
- sd->of_node ? sd->of_node->full_name : "<none>");
-
- sd->dma_ops = pci_dma_ops;
-#ifdef CONFIG_NUMA
- sd->numa_node = pcibus_to_node(dev->bus);
-#else
- sd->numa_node = -1;
-#endif
- if (ppc_md.pci_dma_dev_setup)
- ppc_md.pci_dma_dev_setup(dev);
-}
-EXPORT_SYMBOL(pcibios_setup_new_device);
-
void __devinit pcibios_do_bus_setup(struct pci_bus *bus)
{
struct pci_dev *dev;
diff --git a/include/asm-powerpc/dma-mapping.h
b/include/asm-powerpc/dma-mapping.h
index bbefb69..b177bac 100644
--- a/include/asm-powerpc/dma-mapping.h
+++ b/include/asm-powerpc/dma-mapping.h
@@ -43,9 +43,10 @@ extern void __dma_sync_page(struct page *page, unsigned long
offset,
#endif /* ! CONFIG_NOT_COHERENT_CACHE */
-#ifdef CONFIG_PPC64
+extern struct dma_mapping_ops dma_direct_ops;
+
/*
- * DMA operations are abstracted for G5 vs. i/pSeries, PCI vs. VIO
+ * DMA operations are abstracted for G5 vs. i/pSeries, PCI vs. VIO, etc.
*/
struct dma_mapping_ops {
void * (*alloc_coherent)(struct device *dev, size_t size,
@@ -71,8 +72,18 @@ static inline struct dma_mapping_ops *get_dma_ops(struct
device *dev)
* only ISA DMA device we support is the floppy and we have a hack
* in the floppy driver directly to get a device for us.
*/
- if (unlikely(dev == NULL || dev->archdata.dma_ops == NULL))
+ if (unlikely(dev == NULL))
return NULL;
+
+ /* Some legacy devices don't support archdata dma ops.
+ * Assume those devices can use dma_direct_ops.
+ * This also serves as a default for 32-bit platforms
+ * on which all devices use the direct ops and so we haven't
+ * set up the archdata dma_ops.
+ */
+ if (dev->archdata.dma_ops == NULL)
+ return &dma_direct_ops;
+
return dev->archdata.dma_ops;
}
@@ -192,121 +203,6 @@ static inline void dma_unmap_sg(struct device *dev,
struct scatterlist *sg,
* Available generic sets of operations
*/
extern struct dma_mapping_ops dma_iommu_ops;
-extern struct dma_mapping_ops dma_direct_ops;
-
-#else /* CONFIG_PPC64 */
-
-#define dma_supported(dev, mask) (1)
-
-static inline int dma_set_mask(struct device *dev, u64 dma_mask)
-{
- if (!dev->dma_mask || !dma_supported(dev, mask))
- return -EIO;
-
- *dev->dma_mask = dma_mask;
-
- return 0;
-}
-
-static inline void *dma_alloc_coherent(struct device *dev, size_t size,
- dma_addr_t * dma_handle,
- gfp_t gfp)
-{
-#ifdef CONFIG_NOT_COHERENT_CACHE
- return __dma_alloc_coherent(size, dma_handle, gfp);
-#else
- void *ret;
- /* ignore region specifiers */
- gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
-
- if (dev == NULL || dev->coherent_dma_mask < 0xffffffff)
- gfp |= GFP_DMA;
-
- ret = (void *)__get_free_pages(gfp, get_order(size));
-
- if (ret != NULL) {
- memset(ret, 0, size);
- *dma_handle = virt_to_bus(ret);
- }
-
- return ret;
-#endif
-}
-
-static inline void
-dma_free_coherent(struct device *dev, size_t size, void *vaddr,
- dma_addr_t dma_handle)
-{
-#ifdef CONFIG_NOT_COHERENT_CACHE
- __dma_free_coherent(size, vaddr);
-#else
- free_pages((unsigned long)vaddr, get_order(size));
-#endif
-}
-
-static inline dma_addr_t
-dma_map_single(struct device *dev, void *ptr, size_t size,
- enum dma_data_direction direction)
-{
- BUG_ON(direction == DMA_NONE);
-
- __dma_sync(ptr, size, direction);
-
- return virt_to_bus(ptr);
-}
-
-static inline void dma_unmap_single(struct device *dev, dma_addr_t dma_addr,
- size_t size,
- enum dma_data_direction direction)
-{
- /* We do nothing. */
-}
-
-static inline dma_addr_t
-dma_map_page(struct device *dev, struct page *page,
- unsigned long offset, size_t size,
- enum dma_data_direction direction)
-{
- BUG_ON(direction == DMA_NONE);
-
- __dma_sync_page(page, offset, size, direction);
-
- return page_to_bus(page) + offset;
-}
-
-static inline void dma_unmap_page(struct device *dev, dma_addr_t dma_address,
- size_t size,
- enum dma_data_direction direction)
-{
- /* We do nothing. */
-}
-
-static inline int
-dma_map_sg(struct device *dev, struct scatterlist *sgl, int nents,
- enum dma_data_direction direction)
-{
- struct scatterlist *sg;
- int i;
-
- BUG_ON(direction == DMA_NONE);
-
- for_each_sg(sgl, sg, nents, i) {
- BUG_ON(!sg_page(sg));
- __dma_sync_page(sg_page(sg), sg->offset, sg->length, direction);
- sg->dma_address = page_to_bus(sg_page(sg)) + sg->offset;
- }
-
- return nents;
-}
-
-static inline void dma_unmap_sg(struct device *dev, struct scatterlist *sg,
- int nhwentries,
- enum dma_data_direction direction)
-{
- /* We don't do anything here. */
-}
-
-#endif /* CONFIG_PPC64 */
static inline void dma_sync_single_for_cpu(struct device *dev,
dma_addr_t dma_handle, size_t size,
diff --git a/include/asm-powerpc/machdep.h b/include/asm-powerpc/machdep.h
index 0872ec2..7652495 100644
--- a/include/asm-powerpc/machdep.h
+++ b/include/asm-powerpc/machdep.h
@@ -85,8 +85,6 @@ struct machdep_calls {
unsigned long (*tce_get)(struct iommu_table *tbl,
long index);
void (*tce_flush)(struct iommu_table *tbl);
- void (*pci_dma_dev_setup)(struct pci_dev *dev);
- void (*pci_dma_bus_setup)(struct pci_bus *bus);
void __iomem * (*ioremap)(phys_addr_t addr, unsigned long size,
unsigned long flags);
@@ -98,6 +96,9 @@ struct machdep_calls {
#endif
#endif /* CONFIG_PPC64 */
+ void (*pci_dma_dev_setup)(struct pci_dev *dev);
+ void (*pci_dma_bus_setup)(struct pci_bus *bus);
+
int (*probe)(void);
void (*setup_arch)(void); /* Optional, may be NULL */
void (*init_early)(void);
diff --git a/include/asm-powerpc/pci.h b/include/asm-powerpc/pci.h
index a05a942..0e52c78 100644
--- a/include/asm-powerpc/pci.h
+++ b/include/asm-powerpc/pci.h
@@ -60,6 +60,14 @@ static inline int pci_get_legacy_ide_irq(struct pci_dev
*dev, int channel)
return channel ? 15 : 14;
}
+#ifdef CONFIG_PCI
+extern void set_pci_dma_ops(struct dma_mapping_ops *dma_ops);
+extern struct dma_mapping_ops *get_pci_dma_ops(void);
+#else /* CONFIG_PCI */
+#define set_pci_dma_ops(d)
+#define get_pci_dma_ops() NULL
+#endif
+
#ifdef CONFIG_PPC64
/*
@@ -70,9 +78,6 @@ static inline int pci_get_legacy_ide_irq(struct pci_dev *dev,
int channel)
#define PCI_DISABLE_MWI
#ifdef CONFIG_PCI
-extern void set_pci_dma_ops(struct dma_mapping_ops *dma_ops);
-extern struct dma_mapping_ops *get_pci_dma_ops(void);
-
static inline void pci_dma_burst_advice(struct pci_dev *pdev,
enum pci_dma_burst_strategy *strat,
unsigned long *strategy_parameter)
@@ -89,9 +94,6 @@ static inline void pci_dma_burst_advice(struct pci_dev *pdev,
*strat = PCI_DMA_BURST_MULTIPLE;
*strategy_parameter = cacheline_size;
}
-#else /* CONFIG_PCI */
-#define set_pci_dma_ops(d)
-#define get_pci_dma_ops() NULL
#endif
#else /* 32-bit */
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