From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Fri, 14 Jun 2002 15:57:11 +1000 From: David Gibson To: linuxppc-embedded@lists.linuxppc.org, Paul Mackerras Subject: Re: consistent_free() Message-ID: <20020614055711.GA1124@zax> References: <20020614042928.GK26146@zax> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20020614042928.GK26146@zax> Sender: owner-linuxppc-embedded@lists.linuxppc.org List-Id: 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@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/