qla2xxx: Enable Exchange offload support.

This patch enables Exchange offload support in Qlogic ISP.
To enable exchange offload with Qlogic ISP24XX/25XX/26XX,
set module parameter ql2xexchoffld to any non-zero number.
This will alow ISP firmware to store exchange data structures
used by firmware to host memory provided by driver. ISP firmware
can supports upto 32k total active exchanges.

Signed-off-by: Himanshu Madhani <himanshu.madhani@qlogic.com>
Signed-off-by: Giridhar Malavali <giridhar.malavali@qlogic.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

1 files changed, 78 insertions, 0 deletions

diff --git a/drivers/scsi/qla2xxx/qla_os.c b/drivers/scsi/qla2xxx/qla_os.c
index 3c4af7e10550..266dd746841a 100644
--- a/drivers/scsi/qla2xxx/qla_os.c
+++ b/drivers/scsi/qla2xxx/qla_os.c
@@ -227,6 +227,12 @@ MODULE_PARM_DESC(ql2xexlogins,
 		 "Number of extended Logins. "
 		 "0 (Default)- Disabled.");
 
+int ql2xexchoffld = 0;
+module_param(ql2xexchoffld, uint, S_IRUGO|S_IWUSR);
+MODULE_PARM_DESC(ql2xexchoffld,
+		 "Number of exchanges to offload. "
+		 "0 (Default)- Disabled.");
+
 /*
  * SCSI host template entry points
  */
@@ -3138,6 +3144,10 @@ qla2x00_remove_one(struct pci_dev *pdev)
 	if (ha->exlogin_buf)
 		qla2x00_free_exlogin_buffer(ha);
 
+	/* free DMA memory */
+	if (ha->exchoffld_buf)
+		qla2x00_free_exchoffld_buffer(ha);
+
 	qla2x00_destroy_deferred_work(ha);
 
 	qlt_remove_target(ha, base_vha);
@@ -3663,6 +3673,74 @@ qla2x00_free_exlogin_buffer(struct qla_hw_data *ha)
 	}
 }
 
+int
+qla2x00_set_exchoffld_buffer(scsi_qla_host_t *vha)
+{
+	int rval;
+	uint16_t	size, max_cnt, temp;
+	struct qla_hw_data *ha = vha->hw;
+
+	/* Return if we don't need to alloacate any extended logins */
+	if (!ql2xexchoffld)
+		return QLA_SUCCESS;
+
+	ql_log(ql_log_info, vha, 0xd014,
+	    "Exchange offload count: %d.\n", ql2xexlogins);
+
+	max_cnt = 0;
+	rval = qla_get_exchoffld_status(vha, &size, &max_cnt);
+	if (rval != QLA_SUCCESS) {
+		ql_log_pci(ql_log_fatal, ha->pdev, 0xd012,
+		    "Failed to get exlogin status.\n");
+		return rval;
+	}
+
+	temp = (ql2xexchoffld > max_cnt) ? max_cnt : ql2xexchoffld;
+	ha->exchoffld_size = (size * temp);
+	ql_log(ql_log_info, vha, 0xd016,
+		"Exchange offload: max_count=%d, buffers=0x%x, total=%d.\n",
+		max_cnt, size, temp);
+
+	ql_log(ql_log_info, vha, 0xd017,
+	    "Exchange Buffers requested size = 0x%x\n", ha->exchoffld_size);
+
+	/* Get consistent memory for extended logins */
+	ha->exchoffld_buf = dma_alloc_coherent(&ha->pdev->dev,
+	    ha->exchoffld_size, &ha->exchoffld_buf_dma, GFP_KERNEL);
+	if (!ha->exchoffld_buf) {
+		ql_log_pci(ql_log_fatal, ha->pdev, 0xd013,
+		    "Failed to allocate memory for exchoffld_buf_dma.\n");
+		return -ENOMEM;
+	}
+
+	/* Now configure the dma buffer */
+	rval = qla_set_exchoffld_mem_cfg(vha, ha->exchoffld_buf_dma);
+	if (rval) {
+		ql_log(ql_log_fatal, vha, 0xd02e,
+		    "Setup exchange offload buffer ****FAILED****.\n");
+		qla2x00_free_exchoffld_buffer(ha);
+	}
+
+	return rval;
+}
+
+/*
+* qla2x00_free_exchoffld_buffer
+*
+* Input:
+*	ha = adapter block pointer
+*/
+void
+qla2x00_free_exchoffld_buffer(struct qla_hw_data *ha)
+{
+	if (ha->exchoffld_buf) {
+		dma_free_coherent(&ha->pdev->dev, ha->exchoffld_size,
+		    ha->exchoffld_buf, ha->exchoffld_buf_dma);
+		ha->exchoffld_buf = NULL;
+		ha->exchoffld_size = 0;
+	}
+}
+
 /*
 * qla2x00_free_fw_dump
 *	Frees fw dump stuff.