Hello Thomas,
unlike with sgiseeq.c, in sgiwd93.c there's no need to bloat the hpc_chunk
and only a single dma_cache_sync-call is necessary in fill_hpc_entries and
init_hpc_chain respectively.
kind regards
peter
On Mon, 26 Nov 2007, Thomas Bogendoerfer wrote:
> Date: Mon, 26 Nov 2007 18:41:15 +0100
> From: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx>
> To: linux-scsi@xxxxxxxxxxxxxxx, linux-mips@xxxxxxxxxxxxxx
> Cc: ralf@xxxxxxxxxxxxxx, James.Bottomley@xxxxxxxxxxxxxxxxxxxxx
> Subject: [PATCH] SGIWD93: use cached memory access to make driver work on
> IP28
>
> Following patch is 2.6.25 material needed to get SGI IP28 machines
> supported.
>
> Thomas.
>
> SGI IP28 machines would need special treatment (enable adding addtional
> wait states) when accessing memory uncached. To avoid this pain I
> changed the driver to use only cached access to memory.
>
> Signed-off-by: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx>
> ---
> drivers/scsi/sgiwd93.c | 68 ++++++++++++++++++++++++++++++-----------------
> 1 files changed, 43 insertions(+), 25 deletions(-)
>
> ...
Signed-off-by: peter fuerst <post@xxxxxxxx>
---
diff -up a/drivers/scsi/sgiwd93.c b/drivers/scsi/sgiwd93.c
--- a/drivers/scsi/sgiwd93.c
+++ b/drivers/scsi/sgiwd93.c
@@ -42,15 +42,13 @@ struct ip22_hostdata {
struct hpc_chunk {
struct hpc_dma_desc desc;
- u32 _padding[128/4 - 3]; /* align to biggest cache line size */
+ u32 _padding;
};
/* space for hpc dma descriptors */
-#define HPC_DMA_SIZE (4 * PAGE_SIZE)
+#define HPC_DMA_SIZE PAGE_SIZE
/* we only need to sync the dma descriptor */
-#define DMA_HPC_SYNC(dev, hcp, dir) \
- dma_cache_sync(dev, hcp, sizeof(struct hpc_dma_desc), dir)
#define DMA_DIR(d) ((d == DATA_OUT_DIR) ? DMA_TO_DEVICE : DMA_FROM_DEVICE)
@@ -73,6 +71,7 @@ void fill_hpc_entries(void *dev, struct
void *addr = cmd->SCp.ptr;
dma_addr_t physaddr;
unsigned long count;
+ struct hpc_chunk *hcpstart = hcp;
physaddr = dma_map_single(dev, addr, len, DMA_DIR(datainp));
cmd->SCp.dma_handle = physaddr;
@@ -85,7 +84,6 @@ void fill_hpc_entries(void *dev, struct
count = len > 8192 ? 8192 : len;
hcp->desc.pbuf = physaddr;
hcp->desc.cntinfo = count;
- DMA_HPC_SYNC(dev, hcp, DMA_TO_DEVICE);
hcp++;
len -= count;
physaddr += count;
@@ -98,7 +96,7 @@ void fill_hpc_entries(void *dev, struct
*/
hcp->desc.pbuf = 0;
hcp->desc.cntinfo = HPCDMA_EOX;
- DMA_HPC_SYNC(dev, hcp, DMA_TO_DEVICE);
+ dma_cache_sync(dev, hcpstart, sizeof(*hcp)*(1+hcp-hcpstart), DMA_TO_DEVICE);
}
static int dma_setup(struct scsi_cmnd *cmd, int datainp)
@@ -181,18 +179,17 @@ static inline void init_hpc_chain(void *
unsigned long start, end;
start = (unsigned long) hcp;
- end = start + (4 * PAGE_SIZE);
+ end = start + HPC_DMA_SIZE;
while (start < end) {
hcp->desc.pnext = (u32) (dma + sizeof(struct hpc_chunk));
hcp->desc.cntinfo = HPCDMA_EOX;
- DMA_HPC_SYNC(dev, hcp, DMA_TO_DEVICE);
hcp++;
dma += sizeof(struct hpc_chunk);
start += sizeof(struct hpc_chunk);
};
hcp--;
hcp->desc.pnext = hdata->dma;
- DMA_HPC_SYNC(dev, hcp, DMA_TO_DEVICE);
+ dma_cache_sync(dev, hdata->cpu, HPC_DMA_SIZE, DMA_TO_DEVICE);
}
static int sgiwd93_bus_reset(struct scsi_cmnd *cmd)
