Changes to last version:
- no additional padding of hpc descriptor
- one dma_cache_sync after hpc descriptors are setup is enough
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 | 64 +++++++++++++++++++++++++++++------------------
1 files changed, 39 insertions(+), 25 deletions(-)
diff --git a/drivers/scsi/sgiwd93.c b/drivers/scsi/sgiwd93.c
index eef8275..e64ddee 100644
--- a/drivers/scsi/sgiwd93.c
+++ b/drivers/scsi/sgiwd93.c
@@ -33,10 +33,9 @@
struct ip22_hostdata {
struct WD33C93_hostdata wh;
- struct hpc_data {
- dma_addr_t dma;
- void *cpu;
- } hd;
+ dma_addr_t dma;
+ void *cpu;
+ void *dev;
};
#define host_to_hostdata(host) ((struct ip22_hostdata *)((host)->hostdata))
@@ -46,6 +45,11 @@ struct hpc_chunk {
u32 _padding; /* align to quadword boundary */
};
+/* space for hpc dma descriptors */
+#define HPC_DMA_SIZE PAGE_SIZE
+
+#define DMA_DIR(d) ((d == DATA_OUT_DIR) ? DMA_TO_DEVICE : DMA_FROM_DEVICE)
+
static irqreturn_t sgiwd93_intr(int irq, void *dev_id)
{
struct Scsi_Host * host = dev_id;
@@ -59,15 +63,17 @@ static irqreturn_t sgiwd93_intr(int irq, void *dev_id)
}
static inline
-void fill_hpc_entries(struct hpc_chunk *hcp, struct scsi_cmnd *cmd, int datainp)
+void fill_hpc_entries(struct ip22_hostdata *hd, struct scsi_cmnd *cmd, int din)
{
unsigned long len = cmd->SCp.this_residual;
void *addr = cmd->SCp.ptr;
dma_addr_t physaddr;
unsigned long count;
+ struct hpc_chunk *hcp;
- physaddr = dma_map_single(NULL, addr, len, cmd->sc_data_direction);
+ physaddr = dma_map_single(hd->dev, addr, len, DMA_DIR(din));
cmd->SCp.dma_handle = physaddr;
+ hcp = hd->cpu;
while (len) {
/*
@@ -89,6 +95,9 @@ void fill_hpc_entries(struct hpc_chunk *hcp, struct scsi_cmnd *cmd, int datainp)
*/
hcp->desc.pbuf = 0;
hcp->desc.cntinfo = HPCDMA_EOX;
+ dma_cache_sync(hd->dev, hd->cpu,
+ (unsigned long)(hcp + 1) - (unsigned long)hd->cpu,
+ DMA_TO_DEVICE);
}
static int dma_setup(struct scsi_cmnd *cmd, int datainp)
@@ -96,9 +105,8 @@ static int dma_setup(struct scsi_cmnd *cmd, int datainp)
struct ip22_hostdata *hdata = host_to_hostdata(cmd->device->host);
struct hpc3_scsiregs *hregs =
(struct hpc3_scsiregs *) cmd->device->host->base;
- struct hpc_chunk *hcp = (struct hpc_chunk *) hdata->hd.cpu;
- pr_debug("dma_setup: datainp<%d> hcp<%p> ", datainp, hcp);
+ pr_debug("dma_setup: datainp<%d> hcp<%p> ", datainp, hdata->cpu);
hdata->wh.dma_dir = datainp;
@@ -111,12 +119,12 @@ static int dma_setup(struct scsi_cmnd *cmd, int datainp)
if (cmd->SCp.ptr == NULL || cmd->SCp.this_residual == 0)
return 1;
- fill_hpc_entries(hcp, cmd, datainp);
+ fill_hpc_entries(hdata, cmd, datainp);
pr_debug(" HPCGO\n");
/* Start up the HPC. */
- hregs->ndptr = hdata->hd.dma;
+ hregs->ndptr = hdata->dma;
if (datainp)
hregs->ctrl = HPC3_SCTRL_ACTIVE;
else
@@ -134,6 +142,9 @@ static void dma_stop(struct Scsi_Host *instance, struct scsi_cmnd *SCpnt,
if (!SCpnt)
return;
+ if (SCpnt->SCp.ptr == NULL || SCpnt->SCp.this_residual == 0)
+ return;
+
hregs = (struct hpc3_scsiregs *) SCpnt->device->host->base;
pr_debug("dma_stop: status<%d> ", status);
@@ -145,8 +156,9 @@ static void dma_stop(struct Scsi_Host *instance, struct scsi_cmnd *SCpnt,
barrier();
}
hregs->ctrl = 0;
- dma_unmap_single(NULL, SCpnt->SCp.dma_handle, SCpnt->SCp.this_residual,
- SCpnt->sc_data_direction);
+ dma_unmap_single(hdata->dev, SCpnt->SCp.dma_handle,
+ SCpnt->SCp.this_residual,
+ DMA_DIR(hdata->wh.dma_dir));
pr_debug("\n");
}
@@ -160,22 +172,23 @@ void sgiwd93_reset(unsigned long base)
hregs->ctrl = 0;
}
-static inline void init_hpc_chain(struct hpc_data *hd)
+static inline void init_hpc_chain(void *dev, struct ip22_hostdata *hdata)
{
- struct hpc_chunk *hcp = (struct hpc_chunk *) hd->cpu;
- struct hpc_chunk *dma = (struct hpc_chunk *) hd->dma;
+ struct hpc_chunk *hcp = (struct hpc_chunk *)hdata->cpu;
+ dma_addr_t dma = hdata->dma;
unsigned long start, end;
start = (unsigned long) hcp;
- end = start + PAGE_SIZE;
+ end = start + HPC_DMA_SIZE;
while (start < end) {
- hcp->desc.pnext = (u32) (dma + 1);
+ hcp->desc.pnext = (u32) (dma + sizeof(struct hpc_chunk));
hcp->desc.cntinfo = HPCDMA_EOX;
- hcp++; dma++;
+ hcp++;
+ dma += sizeof(struct hpc_chunk);
start += sizeof(struct hpc_chunk);
};
hcp--;
- hcp->desc.pnext = hd->dma;
+ hcp->desc.pnext = hdata->dma;
}
static int sgiwd93_bus_reset(struct scsi_cmnd *cmd)
@@ -234,16 +247,17 @@ static int __init sgiwd93_probe(struct platform_device *pdev)
host->irq = irq;
hdata = host_to_hostdata(host);
- hdata->hd.cpu = dma_alloc_coherent(&pdev->dev, PAGE_SIZE,
- &hdata->hd.dma, GFP_KERNEL);
- if (!hdata->hd.cpu) {
+ hdata->dev = &pdev->dev;
+ hdata->cpu = dma_alloc_noncoherent(&pdev->dev, HPC_DMA_SIZE,
+ &hdata->dma, GFP_KERNEL);
+ if (!hdata->cpu) {
printk(KERN_WARNING "sgiwd93: Could not allocate memory for "
"host %d buffer.\n", unit);
err = -ENOMEM;
goto out_put;
}
- init_hpc_chain(&hdata->hd);
+ init_hpc_chain(&pdev->dev, hdata);
regs.SASR = wdregs + 3;
regs.SCMD = wdregs + 7;
@@ -273,7 +287,7 @@ static int __init sgiwd93_probe(struct platform_device *pdev)
out_irq:
free_irq(irq, host);
out_free:
- dma_free_coherent(NULL, PAGE_SIZE, hdata->hd.cpu, hdata->hd.dma);
+ dma_free_noncoherent(NULL, HPC_DMA_SIZE, hdata->cpu, hdata->dma);
out_put:
scsi_host_put(host);
out:
@@ -289,7 +303,7 @@ static void __exit sgiwd93_remove(struct platform_device *pdev)
scsi_remove_host(host);
free_irq(pd->irq, host);
- dma_free_coherent(&pdev->dev, PAGE_SIZE, hdata->hd.cpu, hdata->hd.dma);
+ dma_free_noncoherent(&pdev->dev, HPC_DMA_SIZE, hdata->cpu, hdata->dma);
scsi_host_put(host);
}
