On Fri, Jun 14, 2002 at 02:29:28PM +1000, David Gibson wrote:
>
> In attempting to make consistent_alloc/free() work sensibly on
> processors which are cache coherent I ran into a problem.
> consistent_free() doesn't take a size argument. We don't need it in
> the case of not cache coherent processors - in that case
> consistent_alloc() sets up a vm_area() so there's enough information
> to get the size. However for cache coherent processors we probably
> want consistent_alloc() to degenerate to __get_free_pages(), in which
> case consistent_free() must degenerate to free_pages(), which takes a
> size argument.
>
> I suggest we change consistent_free() to take the virtual addresss,
> size and the physical address (dma_addr_t), which will make our
> consistent_free() match the one on ARM. I know we don't need the
> third argument in any existing situation.
>
> Patch coming...
As promised...
This boots up fine on my EP405PC board, and I'm sending this mail from
my TiBook running 2_4_devel with this patch and also the 40x large
page PMD patch.
diff -urN /home/dgibson/kernel/linuxppc_2_4_devel/arch/ppc/kernel/pci-dma.c
linux-grinch/arch/ppc/kernel/pci-dma.c
--- /home/dgibson/kernel/linuxppc_2_4_devel/arch/ppc/kernel/pci-dma.c Fri Jun
14 07:57:36 2002
+++ linux-grinch/arch/ppc/kernel/pci-dma.c Fri Jun 14 14:30:36 2002
@@ -25,28 +25,16 @@
if (hwdev == NULL || hwdev->dma_mask != 0xffffffff)
gfp |= GFP_DMA;
-
-#ifdef CONFIG_NOT_COHERENT_CACHE
ret = consistent_alloc(gfp, size, dma_handle);
-#else
- ret = (void *)__get_free_pages(gfp, get_order(size));
-#endif
- if (ret != NULL) {
+ if (ret != NULL)
memset(ret, 0, size);
-#ifndef CONFIG_NOT_COHERENT_CACHE
- *dma_handle = virt_to_bus(ret);
-#endif
- }
+
return ret;
}
void pci_free_consistent(struct pci_dev *hwdev, size_t size,
void *vaddr, dma_addr_t dma_handle)
{
-#ifdef CONFIG_NOT_COHERENT_CACHE
- consistent_free(vaddr);
-#else
- free_pages((unsigned long)vaddr, get_order(size));
-#endif
+ consistent_free(vaddr, size, dma_handle);
}
diff -urN /home/dgibson/kernel/linuxppc_2_4_devel/arch/ppc/kernel/ppc4xx_dma.c
linux-grinch/arch/ppc/kernel/ppc4xx_dma.c
--- /home/dgibson/kernel/linuxppc_2_4_devel/arch/ppc/kernel/ppc4xx_dma.c
Fri Jun 7 15:26:47 2002
+++ linux-grinch/arch/ppc/kernel/ppc4xx_dma.c Fri Jun 14 14:36:12 2002
@@ -457,6 +457,7 @@
free_dma_handle(sgl_handle_t handle)
{
sgl_list_info_t *psgl = (sgl_list_info_t *) handle;
+ dma_addr_t dma_addr;
if (!handle) {
#ifdef DEBUG_4xxDMA
@@ -475,7 +476,8 @@
return;
}
- consistent_free((void *) psgl);
+ dma_addr = psql->dma_addr;
+ consistent_free((void *) psgl, DMA_PPC4xx_SIZE, dma_addr);
}
EXPORT_SYMBOL(hw_init_dma_channel);
diff -urN /home/dgibson/kernel/linuxppc_2_4_devel/arch/ppc/mm/cachemap.c
linux-grinch/arch/ppc/mm/cachemap.c
--- /home/dgibson/kernel/linuxppc_2_4_devel/arch/ppc/mm/cachemap.c Thu Jun
13 13:40:03 2002
+++ linux-grinch/arch/ppc/mm/cachemap.c Fri Jun 14 15:54:36 2002
@@ -121,7 +121,7 @@
/*
* free page(s) as defined by the above mapping.
*/
-void consistent_free(void *vaddr)
+void consistent_free(void *vaddr, size_t size, dma_addr_t handle)
{
if (in_interrupt())
BUG();
diff -urN
/home/dgibson/kernel/linuxppc_2_4_devel/drivers/net/ibm_ocp/ibm_ocp_enet.c
linux-grinch/drivers/net/ibm_ocp/ibm_ocp_enet.c
--- /home/dgibson/kernel/linuxppc_2_4_devel/drivers/net/ibm_ocp/ibm_ocp_enet.c
Thu Jun 13 10:18:47 2002
+++ linux-grinch/drivers/net/ibm_ocp/ibm_ocp_enet.c Fri Jun 14 14:39:09 2002
@@ -1185,8 +1185,9 @@
/*
* Unmap the non cached memory space.
*/
- consistent_free((void *) tx_virt_addr);
- consistent_free((void *) rx_virt_addr);
+
+ consistent_free(tx_virt_addr, PAGE_SIZE * emac_max, tx_phys_addr);
+ consistent_free(rx_virt_addr, PAGE_SIZE * emac_max, rx_phys_addr);
}
diff -urN /home/dgibson/kernel/linuxppc_2_4_devel/include/asm-ppc/io.h
linux-grinch/include/asm-ppc/io.h
--- /home/dgibson/kernel/linuxppc_2_4_devel/include/asm-ppc/io.h Sat May
11 02:02:08 2002
+++ linux-grinch/include/asm-ppc/io.h Fri Jun 14 14:54:20 2002
@@ -436,7 +436,7 @@
* to ensure it is consistent.
*/
extern void *consistent_alloc(int gfp, size_t size, dma_addr_t *handle);
-extern void consistent_free(void *vaddr);
+extern void consistent_free(void *vaddr, size_t size, dma_addr_t handle);
extern void consistent_sync(void *vaddr, size_t size, int rw);
extern void consistent_sync_page(struct page *page, unsigned long offset,
size_t size, int rw);
@@ -458,8 +458,17 @@
#define dma_cache_wback(_start,_size) do { } while (0)
#define dma_cache_wback_inv(_start,_size) do { } while (0)
-#define consistent_alloc(gfp, size, handle) NULL
-#define consistent_free(addr, size) do { } while (0)
+static inline void *consistent_alloc(int gfp, size_t size, dma_addr_t
*dma_handle)
+{
+ void *vaddr;
+
+ vaddr = (void *)__get_free_pages(gfp, get_order(size));
+ if (vaddr)
+ *dma_handle = virt_to_bus(vaddr);
+ return vaddr;
+}
+
+#define consistent_free(addr, size, dmaddr) free_pages((unsigned long)addr,
get_order(size))
#define consistent_sync(addr, size, rw) do { } while (0)
#define consistent_sync_page(pg, off, sz, rw) do { } while (0)
--
David Gibson | For every complex problem there is a
david at gibson.dropbear.id.au | solution which is simple, neat and
| wrong. -- H.L. Mencken
http://www.ozlabs.org/people/dgibson
** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/
