[SCSI] zfcp: Enable data division support for FCP devices

Try to enable data division support for FCP devices and indicate in
the adapter status flag if it succeeded.

Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

4 files changed, 19 insertions, 1 deletions

diff --git a/arch/s390/include/asm/qdio.h b/arch/s390/include/asm/qdio.h
index 0eaae6260274..2ba630276295 100644
--- a/arch/s390/include/asm/qdio.h
+++ b/arch/s390/include/asm/qdio.h
@@ -84,6 +84,7 @@ struct qdr {
 
 #define QIB_AC_OUTBOUND_PCI_SUPPORTED   0x40
 #define QIB_RFLAGS_ENABLE_QEBSM         0x80
+#define QIB_RFLAGS_ENABLE_DATA_DIV      0x02
 
 /**
  * struct qib - queue information block (QIB)
@@ -284,6 +285,9 @@ struct slsb {
         u8 val[QDIO_MAX_BUFFERS_PER_Q];
 } __attribute__ ((packed, aligned(256)));
 
+#define CHSC_AC2_DATA_DIV_AVAILABLE     0x0010
+#define CHSC_AC2_DATA_DIV_ENABLED       0x0002
+
 struct qdio_ssqd_desc {
         u8 flags;
         u8:8;
@@ -332,6 +336,7 @@ typedef void qdio_handler_t(struct ccw_device *, unsigned int, int,
  * @adapter_name: name for the adapter
  * @qib_param_field_format: format for qib_parm_field
  * @qib_param_field: pointer to 128 bytes or NULL, if no param field
+ * @qib_rflags: rflags to set
  * @input_slib_elements: pointer to no_input_qs * 128 words of data or NULL
  * @output_slib_elements: pointer to no_output_qs * 128 words of data or NULL
  * @no_input_qs: number of input queues
@@ -348,6 +353,7 @@ struct qdio_initialize {
         unsigned char adapter_name[8];
         unsigned int qib_param_field_format;
         unsigned char *qib_param_field;
+        unsigned char qib_rflags;
         unsigned long *input_slib_elements;
         unsigned long *output_slib_elements;
         unsigned int no_input_qs;
diff --git a/drivers/s390/cio/qdio_setup.c b/drivers/s390/cio/qdio_setup.c
index 6326b67c45d2..34c7e4046df4 100644
--- a/drivers/s390/cio/qdio_setup.c
+++ b/drivers/s390/cio/qdio_setup.c
@@ -368,6 +368,8 @@ static void setup_qib(struct qdio_irq *irq_ptr,
         if (qebsm_possible())
                 irq_ptr->qib.rflags |= QIB_RFLAGS_ENABLE_QEBSM;
 
+        irq_ptr->qib.rflags |= init_data->qib_rflags;
+
         irq_ptr->qib.qfmt = init_data->q_format;
         if (init_data->no_input_qs)
                 irq_ptr->qib.isliba =
diff --git a/drivers/s390/scsi/zfcp_def.h b/drivers/s390/scsi/zfcp_def.h
index cb3640c6477c..6c6374ba1807 100644
--- a/drivers/s390/scsi/zfcp_def.h
+++ b/drivers/s390/scsi/zfcp_def.h
@@ -77,6 +77,7 @@ struct zfcp_reqlist;
 #define ZFCP_STATUS_ADAPTER_HOST_CON_INIT       0x00000010
 #define ZFCP_STATUS_ADAPTER_ERP_PENDING         0x00000100
 #define ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED      0x00000200
+#define ZFCP_STATUS_ADAPTER_DATA_DIV_ENABLED    0x00000400
 
 /* remote port status */
 #define ZFCP_STATUS_PORT_PHYS_OPEN              0x00000001
diff --git a/drivers/s390/scsi/zfcp_qdio.c b/drivers/s390/scsi/zfcp_qdio.c
index a638278c6025..c4559b29bebc 100644
--- a/drivers/s390/scsi/zfcp_qdio.c
+++ b/drivers/s390/scsi/zfcp_qdio.c
@@ -283,6 +283,7 @@ static void zfcp_qdio_setup_init_data(struct qdio_initialize *id,
         id->q_format = QDIO_ZFCP_QFMT;
         memcpy(id->adapter_name, dev_name(&id->cdev->dev), 8);
         ASCEBC(id->adapter_name, 8);
+        id->qib_rflags = QIB_RFLAGS_ENABLE_DATA_DIV;
         id->qib_param_field_format = 0;
         id->qib_param_field = NULL;
         id->input_slib_elements = NULL;
@@ -294,8 +295,8 @@ static void zfcp_qdio_setup_init_data(struct qdio_initialize *id,
         id->int_parm = (unsigned long) qdio;
         id->input_sbal_addr_array = (void **) (qdio->res_q);
         id->output_sbal_addr_array = (void **) (qdio->req_q);
-
 }
+
 /**
  * zfcp_qdio_allocate - allocate queue memory and initialize QDIO data
  * @adapter: pointer to struct zfcp_adapter
@@ -358,6 +359,7 @@ int zfcp_qdio_open(struct zfcp_qdio *qdio)
         struct qdio_initialize init_data;
         struct zfcp_adapter *adapter = qdio->adapter;
         struct ccw_device *cdev = adapter->ccw_device;
+        struct qdio_ssqd_desc ssqd;
         int cc;
 
         if (atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP)
@@ -368,6 +370,13 @@ int zfcp_qdio_open(struct zfcp_qdio *qdio)
         if (qdio_establish(&init_data))
                 goto failed_establish;
 
+        if (qdio_get_ssqd_desc(init_data.cdev, &ssqd))
+                goto failed_qdio;
+
+        if (ssqd.qdioac2 & CHSC_AC2_DATA_DIV_ENABLED)
+                atomic_set_mask(ZFCP_STATUS_ADAPTER_DATA_DIV_ENABLED,
+                                &qdio->adapter->status);
+
         if (qdio_activate(cdev))
                 goto failed_qdio;