[PATCH] libata: Support chips with 64K PRD quirk
From: Alan Cox
Date: Tue Jul 03 2007 - 10:59:16 EST
Add ata_dumb_qc_prep and supporting logic so that a driver can just
specify it needs to be helped in this area. 64K entries are split
as with drivers/ide.
Signed-off-by: Alan Cox <alan@xxxxxxxxxx>
diff -u --new-file --exclude-from /usr/src/exclude --recursive linux.vanilla-2.6.22-rc6-mm1/drivers/ata/libata-core.c linux-2.6.22-rc6-mm1/drivers/ata/libata-core.c
--- linux.vanilla-2.6.22-rc6-mm1/drivers/ata/libata-core.c 2007-07-02 20:50:11.000000000 +0100
+++ linux-2.6.22-rc6-mm1/drivers/ata/libata-core.c 2007-07-02 21:36:20.000000000 +0100
@@ -4111,6 +4165,68 @@
if (idx)
ap->prd[idx - 1].flags_len |= cpu_to_le32(ATA_PRD_EOT);
}
+
+/**
+ * ata_fill_sg_dumb - Fill PCI IDE PRD table
+ * @qc: Metadata associated with taskfile to be transferred
+ *
+ * Fill PCI IDE PRD (scatter-gather) table with segments
+ * associated with the current disk command. Perform the fill
+ * so that we avoid writing any length 64K records for
+ * controllers that don't follow the spec.
+ *
+ * LOCKING:
+ * spin_lock_irqsave(host lock)
+ *
+ */
+static void ata_fill_sg_dumb(struct ata_queued_cmd *qc)
+{
+ struct ata_port *ap = qc->ap;
+ struct scatterlist *sg;
+ unsigned int idx;
+
+ WARN_ON(qc->__sg == NULL);
+ WARN_ON(qc->n_elem == 0 && qc->pad_len == 0);
+
+ idx = 0;
+ ata_for_each_sg(sg, qc) {
+ u32 addr, offset;
+ u32 sg_len, len, blen;
+
+ /* determine if physical DMA addr spans 64K boundary.
+ * Note h/w doesn't support 64-bit, so we unconditionally
+ * truncate dma_addr_t to u32.
+ */
+ addr = (u32) sg_dma_address(sg);
+ sg_len = sg_dma_len(sg);
+
+ while (sg_len) {
+ offset = addr & 0xffff;
+ len = sg_len;
+ if ((offset + sg_len) > 0x10000)
+ len = 0x10000 - offset;
+
+ blen = len & 0xffff;
+ ap->prd[idx].addr = cpu_to_le32(addr);
+ if (blen == 0) {
+ /* Some PATA chipsets like the CS5530 can't
+ cope with 0x0000 meaning 64K as the spec says */
+ ap->prd[idx].flags_len = cpu_to_le32(0x8000);
+ blen = 0x8000;
+ ap->prd[++idx].addr = cpu_to_le32(addr + 0x8000);
+ }
+ ap->prd[idx].flags_len = cpu_to_le32(blen);
+ VPRINTK("PRD[%u] = (0x%X, 0x%X)\n", idx, addr, len);
+
+ idx++;
+ sg_len -= len;
+ addr += len;
+ }
+ }
+
+ if (idx)
+ ap->prd[idx - 1].flags_len |= cpu_to_le32(ATA_PRD_EOT);
+}
/**
* ata_check_atapi_dma - Check whether ATAPI DMA can be supported
@@ -4159,6 +4275,23 @@
ata_fill_sg(qc);
}
+/**
+ * ata_dumb_qc_prep - Prepare taskfile for submission
+ * @qc: Metadata associated with taskfile to be prepared
+ *
+ * Prepare ATA taskfile for submission.
+ *
+ * LOCKING:
+ * spin_lock_irqsave(host lock)
+ */
+void ata_dumb_qc_prep(struct ata_queued_cmd *qc)
+{
+ if (!(qc->flags & ATA_QCFLAG_DMAMAP))
+ return;
+
+ ata_fill_sg_dumb(qc);
+}
+
void ata_noop_qc_prep(struct ata_queued_cmd *qc) { }
/**
diff -u --new-file --exclude-from /usr/src/exclude --recursive linux.vanilla-2.6.22-rc6-mm1/include/linux/libata.h linux-2.6.22-rc6-mm1/include/linux/libata.h
--- linux.vanilla-2.6.22-rc6-mm1/include/linux/libata.h 2007-07-02 20:50:14.000000000 +0100
+++ linux-2.6.22-rc6-mm1/include/linux/libata.h 2007-07-02 21:29:18.000000000 +0100
@@ -116,6 +116,7 @@
enum {
/* various global constants */
LIBATA_MAX_PRD = ATA_MAX_PRD / 2,
+ LIBATA_DUMB_MAX_PRD = ATA_MAX_PRD / 4, /* Worst case */
ATA_MAX_PORTS = 8,
ATA_DEF_QUEUE = 1,
/* tag ATA_MAX_QUEUE - 1 is reserved for internal commands */
@@ -785,6 +789,7 @@
unsigned int buflen, int write_data);
extern void ata_data_xfer_noirq(struct ata_device *adev, unsigned char *buf,
unsigned int buflen, int write_data);
+extern void ata_dumb_qc_prep(struct ata_queued_cmd *qc);
extern void ata_qc_prep(struct ata_queued_cmd *qc);
extern void ata_noop_qc_prep(struct ata_queued_cmd *qc);
extern unsigned int ata_qc_issue_prot(struct ata_queued_cmd *qc);
diff -u --new-file --exclude-from /usr/src/exclude --recursive linux.vanilla-2.6.22-rc6-mm1/drivers/ata/pata_cs5520.c linux-2.6.22-rc6-mm1/drivers/ata/pata_cs5520.c
--- linux.vanilla-2.6.22-rc6-mm1/drivers/ata/pata_cs5520.c 2007-07-02 20:48:49.000000000 +0100
+++ linux-2.6.22-rc6-mm1/drivers/ata/pata_cs5520.c 2007-07-02 21:03:00.000000000 +0100
@@ -146,7 +146,7 @@
.queuecommand = ata_scsi_queuecmd,
.can_queue = ATA_DEF_QUEUE,
.this_id = ATA_SHT_THIS_ID,
- .sg_tablesize = LIBATA_MAX_PRD,
+ .sg_tablesize = LIBATA_DUMB_MAX_PRD,
.cmd_per_lun = ATA_SHT_CMD_PER_LUN,
.emulated = ATA_SHT_EMULATED,
.use_clustering = ATA_SHT_USE_CLUSTERING,
@@ -178,7 +178,7 @@
.bmdma_start = ata_bmdma_start,
.bmdma_stop = ata_bmdma_stop,
.bmdma_status = ata_bmdma_status,
- .qc_prep = ata_qc_prep,
+ .qc_prep = ata_dumb_qc_prep,
.qc_issue = ata_qc_issue_prot,
.data_xfer = ata_data_xfer,
diff -u --new-file --exclude-from /usr/src/exclude --recursive linux.vanilla-2.6.22-rc6-mm1/drivers/ata/pata_cs5530.c linux-2.6.22-rc6-mm1/drivers/ata/pata_cs5530.c
--- linux.vanilla-2.6.22-rc6-mm1/drivers/ata/pata_cs5530.c 2007-07-02 20:50:11.000000000 +0100
+++ linux-2.6.22-rc6-mm1/drivers/ata/pata_cs5530.c 2007-07-02 21:03:00.000000000 +0100
@@ -167,7 +167,7 @@
.queuecommand = ata_scsi_queuecmd,
.can_queue = ATA_DEF_QUEUE,
.this_id = ATA_SHT_THIS_ID,
- .sg_tablesize = LIBATA_MAX_PRD,
+ .sg_tablesize = LIBATA_DUMB_MAX_PRD,
.cmd_per_lun = ATA_SHT_CMD_PER_LUN,
.emulated = ATA_SHT_EMULATED,
.use_clustering = ATA_SHT_USE_CLUSTERING,
@@ -201,7 +201,7 @@
.post_internal_cmd = ata_bmdma_post_internal_cmd,
.cable_detect = ata_cable_40wire,
- .qc_prep = ata_qc_prep,
+ .qc_prep = ata_dumb_qc_prep,
.qc_issue = cs5530_qc_issue_prot,
.data_xfer = ata_data_xfer,
diff -u --new-file --exclude-from /usr/src/exclude --recursive linux.vanilla-2.6.22-rc6-mm1/drivers/ata/pata_sc1200.c linux-2.6.22-rc6-mm1/drivers/ata/pata_sc1200.c
--- linux.vanilla-2.6.22-rc6-mm1/drivers/ata/pata_sc1200.c 2007-07-02 20:50:11.000000000 +0100
+++ linux-2.6.22-rc6-mm1/drivers/ata/pata_sc1200.c 2007-07-02 21:04:59.000000000 +0100
@@ -185,7 +185,7 @@
.queuecommand = ata_scsi_queuecmd,
.can_queue = ATA_DEF_QUEUE,
.this_id = ATA_SHT_THIS_ID,
- .sg_tablesize = LIBATA_MAX_PRD,
+ .sg_tablesize = LIBATA_DUMB_MAX_PRD,
.cmd_per_lun = ATA_SHT_CMD_PER_LUN,
.emulated = ATA_SHT_EMULATED,
.use_clustering = ATA_SHT_USE_CLUSTERING,
@@ -219,7 +219,7 @@
.bmdma_stop = ata_bmdma_stop,
.bmdma_status = ata_bmdma_status,
- .qc_prep = ata_qc_prep,
+ .qc_prep = ata_dumb_qc_prep,
.qc_issue = sc1200_qc_issue_prot,
.data_xfer = ata_data_xfer,
-
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