NTB: Handle 64bit BAR sizes

64bit BAR sizes are permissible with an NTB device.  To support them
various modifications and clean-ups were required, most significantly
using 2 32bit scratch pad registers for each BAR.

Also, modify the driver to allow more than 2 Memory Windows.

Signed-off-by: Jon Mason <jon.mason@intel.com>

1 files changed, 73 insertions, 48 deletions

diff --git a/drivers/ntb/ntb_transport.c b/drivers/ntb/ntb_transport.c
index 00f5e80dee35..79a3203eccd9 100644
--- a/drivers/ntb/ntb_transport.c
+++ b/drivers/ntb/ntb_transport.c
@@ -58,7 +58,7 @@
 #include <linux/ntb.h>
 #include "ntb_hw.h"
 
-#define NTB_TRANSPORT_VERSION   2
+#define NTB_TRANSPORT_VERSION   3
 
 static unsigned int transport_mtu = 0x401E;
 module_param(transport_mtu, uint, 0644);
@@ -173,10 +173,13 @@ struct ntb_payload_header {
 
 enum {
         VERSION = 0,
-        MW0_SZ,
-        MW1_SZ,
-        NUM_QPS,
         QP_LINKS,
+        NUM_QPS,
+        NUM_MWS,
+        MW0_SZ_HIGH,
+        MW0_SZ_LOW,
+        MW1_SZ_HIGH,
+        MW1_SZ_LOW,
         MAX_SPAD,
 };
 
@@ -526,6 +529,18 @@ static int ntb_set_mw(struct ntb_transport *nt, int num_mw, unsigned int size)
         return 0;
 }
 
+static void ntb_free_mw(struct ntb_transport *nt, int num_mw)
+{
+        struct ntb_transport_mw *mw = &nt->mw[num_mw];
+        struct pci_dev *pdev = ntb_query_pdev(nt->ndev);
+
+        if (!mw->virt_addr)
+                return;
+
+        dma_free_coherent(&pdev->dev, mw->size, mw->virt_addr, mw->dma_addr);
+        mw->virt_addr = NULL;
+}
+
 static void ntb_qp_link_cleanup(struct work_struct *work)
 {
         struct ntb_transport_qp *qp = container_of(work,
@@ -604,25 +619,31 @@ static void ntb_transport_link_work(struct work_struct *work)
         u32 val;
         int rc, i;
 
-        /* send the local info */
-        rc = ntb_write_remote_spad(ndev, VERSION, NTB_TRANSPORT_VERSION);
-        if (rc) {
-                dev_err(&pdev->dev, "Error writing %x to remote spad %d\n",
-                        0, VERSION);
-                goto out;
-        }
+        /* send the local info, in the opposite order of the way we read it */
+        for (i = 0; i < NTB_NUM_MW; i++) {
+                rc = ntb_write_remote_spad(ndev, MW0_SZ_HIGH + (i * 2),
+                                           ntb_get_mw_size(ndev, i) >> 32);
+                if (rc) {
+                        dev_err(&pdev->dev, "Error writing %u to remote spad %d\n",
+                                (u32)(ntb_get_mw_size(ndev, i) >> 32),
+                                MW0_SZ_HIGH + (i * 2));
+                        goto out;
+                }
 
-        rc = ntb_write_remote_spad(ndev, MW0_SZ, ntb_get_mw_size(ndev, 0));
-        if (rc) {
-                dev_err(&pdev->dev, "Error writing %x to remote spad %d\n",
-                        (u32) ntb_get_mw_size(ndev, 0), MW0_SZ);
-                goto out;
+                rc = ntb_write_remote_spad(ndev, MW0_SZ_LOW + (i * 2),
+                                           (u32) ntb_get_mw_size(ndev, i));
+                if (rc) {
+                        dev_err(&pdev->dev, "Error writing %u to remote spad %d\n",
+                                (u32) ntb_get_mw_size(ndev, i),
+                                MW0_SZ_LOW + (i * 2));
+                        goto out;
+                }
         }
 
-        rc = ntb_write_remote_spad(ndev, MW1_SZ, ntb_get_mw_size(ndev, 1));
+        rc = ntb_write_remote_spad(ndev, NUM_MWS, NTB_NUM_MW);
         if (rc) {
                 dev_err(&pdev->dev, "Error writing %x to remote spad %d\n",
-                        (u32) ntb_get_mw_size(ndev, 1), MW1_SZ);
+                        NTB_NUM_MW, NUM_MWS);
                 goto out;
         }
 
@@ -633,16 +654,10 @@ static void ntb_transport_link_work(struct work_struct *work)
                 goto out;
         }
 
-        rc = ntb_read_local_spad(nt->ndev, QP_LINKS, &val);
-        if (rc) {
-                dev_err(&pdev->dev, "Error reading spad %d\n", QP_LINKS);
-                goto out;
-        }
-
-        rc = ntb_write_remote_spad(ndev, QP_LINKS, val);
+        rc = ntb_write_remote_spad(ndev, VERSION, NTB_TRANSPORT_VERSION);
         if (rc) {
                 dev_err(&pdev->dev, "Error writing %x to remote spad %d\n",
-                        val, QP_LINKS);
+                        NTB_TRANSPORT_VERSION, VERSION);
                 goto out;
         }
 
@@ -667,33 +682,43 @@ static void ntb_transport_link_work(struct work_struct *work)
                 goto out;
         dev_dbg(&pdev->dev, "Remote max number of qps = %d\n", val);
 
-        rc = ntb_read_remote_spad(ndev, MW0_SZ, &val);
+        rc = ntb_read_remote_spad(ndev, NUM_MWS, &val);
         if (rc) {
-                dev_err(&pdev->dev, "Error reading remote spad %d\n", MW0_SZ);
+                dev_err(&pdev->dev, "Error reading remote spad %d\n", NUM_MWS);
                 goto out;
         }
 
-        if (!val)
+        if (val != NTB_NUM_MW)
                 goto out;
-        dev_dbg(&pdev->dev, "Remote MW0 size = %d\n", val);
+        dev_dbg(&pdev->dev, "Remote number of mws = %d\n", val);
 
-        rc = ntb_set_mw(nt, 0, val);
-        if (rc)
-                goto out;
+        for (i = 0; i < NTB_NUM_MW; i++) {
+                u64 val64;
 
-        rc = ntb_read_remote_spad(ndev, MW1_SZ, &val);
-        if (rc) {
-                dev_err(&pdev->dev, "Error reading remote spad %d\n", MW1_SZ);
-                goto out;
-        }
+                rc = ntb_read_remote_spad(ndev, MW0_SZ_HIGH + (i * 2), &val);
+                if (rc) {
+                        dev_err(&pdev->dev, "Error reading remote spad %d\n",
+                                MW0_SZ_HIGH + (i * 2));
+                        goto out1;
+                }
 
-        if (!val)
-                goto out;
-        dev_dbg(&pdev->dev, "Remote MW1 size = %d\n", val);
+                val64 = (u64) val << 32;
 
-        rc = ntb_set_mw(nt, 1, val);
-        if (rc)
-                goto out;
+                rc = ntb_read_remote_spad(ndev, MW0_SZ_LOW + (i * 2), &val);
+                if (rc) {
+                        dev_err(&pdev->dev, "Error reading remote spad %d\n",
+                                MW0_SZ_LOW + (i * 2));
+                        goto out1;
+                }
+
+                val64 |= val;
+
+                dev_dbg(&pdev->dev, "Remote MW%d size = %llu\n", i, val64);
+
+                rc = ntb_set_mw(nt, i, val64);
+                if (rc)
+                        goto out1;
+        }
 
         nt->transport_link = NTB_LINK_UP;
 
@@ -708,6 +733,9 @@ static void ntb_transport_link_work(struct work_struct *work)
 
         return;
 
+out1:
+        for (i = 0; i < NTB_NUM_MW; i++)
+                ntb_free_mw(nt, i);
 out:
         if (ntb_hw_link_status(ndev))
                 schedule_delayed_work(&nt->link_work,
@@ -897,10 +925,7 @@ void ntb_transport_free(void *transport)
         pdev = ntb_query_pdev(nt->ndev);
 
         for (i = 0; i < NTB_NUM_MW; i++)
-                if (nt->mw[i].virt_addr)
-                        dma_free_coherent(&pdev->dev, nt->mw[i].size,
-                                          nt->mw[i].virt_addr,
-                                          nt->mw[i].dma_addr);
+                ntb_free_mw(nt, i);
 
         kfree(nt->qps);
         ntb_unregister_transport(nt->ndev);