pci-epf-vntb can pack multiple memory windows into a single BAR using
mwN_offset. With the NTB core gaining support for programming multiple
translation ranges for a window, the EPF needs to provide the per-BAR
subrange layout to the endpoint controller (EPC).

Implement .mw_set_trans_ranges() for pci-epf-vntb. Track subranges for
each BAR and pass them to pci_epc_set_bar() so EPC drivers can select an
appropriate inbound mapping mode (e.g. Address Match mode on DesignWare
controllers) when subrange mappings are required.

Signed-off-by: Koichiro Den <[email protected]>
---
 drivers/pci/endpoint/functions/pci-epf-vntb.c | 183 +++++++++++++++++-
 1 file changed, 175 insertions(+), 8 deletions(-)

diff --git a/drivers/pci/endpoint/functions/pci-epf-vntb.c 
b/drivers/pci/endpoint/functions/pci-epf-vntb.c
index 39e784e21236..98128c2c5079 100644
--- a/drivers/pci/endpoint/functions/pci-epf-vntb.c
+++ b/drivers/pci/endpoint/functions/pci-epf-vntb.c
@@ -42,6 +42,7 @@
 #include <linux/log2.h>
 #include <linux/module.h>
 #include <linux/slab.h>
+#include <linux/sort.h>
 
 #include <linux/pci-ep-msi.h>
 #include <linux/pci-epc.h>
@@ -144,6 +145,10 @@ struct epf_ntb {
 
        enum pci_barno epf_ntb_bar[VNTB_BAR_NUM];
 
+       /* Cache for subrange mapping */
+       struct ntb_mw_subrange *mw_subrange[MAX_MW];
+       unsigned int num_subrange[MAX_MW];
+
        struct epf_ntb_ctrl *reg;
 
        u32 *epf_db;
@@ -736,6 +741,7 @@ static int epf_ntb_mw_bar_init(struct epf_ntb *ntb)
                ntb->epf->bar[barno].flags |= upper_32_bits(size) ?
                                PCI_BASE_ADDRESS_MEM_TYPE_64 :
                                PCI_BASE_ADDRESS_MEM_TYPE_32;
+               ntb->epf->bar[barno].num_submap = 0;
 
                ret = pci_epc_set_bar(ntb->epf->epc,
                                      ntb->epf->func_no,
@@ -1405,28 +1411,188 @@ static int vntb_epf_db_set_mask(struct ntb_dev *ntb, 
u64 db_bits)
        return 0;
 }
 
-static int vntb_epf_mw_set_trans(struct ntb_dev *ndev, int pidx, int idx,
-               dma_addr_t addr, resource_size_t size)
+struct vntb_mw_order {
+       u64 off;
+       unsigned int mw;
+};
+
+static int vntb_cmp_mw_order(const void *a, const void *b)
+{
+       const struct vntb_mw_order *ma = a;
+       const struct vntb_mw_order *mb = b;
+
+       if (ma->off < mb->off)
+               return -1;
+       if (ma->off > mb->off)
+               return 1;
+       return 0;
+}
+
+static int vntb_epf_mw_set_trans_ranges(struct ntb_dev *ndev, int pidx, int 
idx,
+                                       unsigned int num_ranges,
+                                       const struct ntb_mw_subrange *ranges)
 {
        struct epf_ntb *ntb = ntb_ndev(ndev);
+       struct pci_epf_bar_submap *submap;
+       struct vntb_mw_order mws[MAX_MW];
        struct pci_epf_bar *epf_bar;
+       struct ntb_mw_subrange *r;
        enum pci_barno barno;
+       struct device *dev, *epf_dev;
+       unsigned int total_ranges = 0;
+       unsigned int mw_cnt = 0;
+       unsigned int cur = 0;
+       u64 expected_off = 0;
+       unsigned int i, j;
        int ret;
+
+       dev = &ntb->ntb->dev;
+       epf_dev = &ntb->epf->dev;
+       barno = ntb->epf_ntb_bar[BAR_MW1 + idx];
+       epf_bar = &ntb->epf->bar[barno];
+       epf_bar->barno = barno;
+
+       r = devm_kmemdup(epf_dev, ranges, num_ranges * sizeof(*ranges), 
GFP_KERNEL);
+       if (!r)
+               return -ENOMEM;
+
+       if (ntb->mw_subrange[idx])
+               devm_kfree(epf_dev, ntb->mw_subrange[idx]);
+
+       ntb->mw_subrange[idx] = r;
+       ntb->num_subrange[idx] = num_ranges;
+
+       /* Defer pci_epc_set_bar() until all MWs in this BAR have range info. */
+       for (i = 0; i < MAX_MW; i++) {
+               enum pci_barno bar = ntb->epf_ntb_bar[BAR_MW1 + i];
+
+               if (bar != barno)
+                       continue;
+               if (!ntb->num_subrange[i])
+                       return 0;
+
+               mws[mw_cnt].mw = i;
+               mws[mw_cnt].off = ntb->mws_offset[i];
+               mw_cnt++;
+       }
+
+       sort(mws, mw_cnt, sizeof(mws[0]), vntb_cmp_mw_order, NULL);
+
+       /* BAR submap must cover the whole BAR with no holes. */
+       for (i = 0; i < mw_cnt; i++) {
+               unsigned int mw = mws[i].mw;
+               u64 sum = 0;
+
+               if (mws[i].off != expected_off) {
+                       dev_err(dev,
+                               "BAR%d: hole/overlap at %#llx (MW%d@%#llx)\n",
+                               barno, expected_off, mw + 1, mws[i].off);
+                       return -EINVAL;
+               }
+
+               total_ranges += ntb->num_subrange[mw];
+               for (j = 0; j < ntb->num_subrange[mw]; j++)
+                       sum += ntb->mw_subrange[mw][j].size;
+
+               if (sum != ntb->mws_size[mw]) {
+                       dev_err(dev,
+                               "MW%d: ranges size %#llx != window size 
%#llx\n",
+                               mw + 1, sum, ntb->mws_size[mw]);
+                       return -EINVAL;
+               }
+               expected_off += ntb->mws_size[mw];
+       }
+
+       submap = devm_krealloc_array(epf_dev, epf_bar->submap, total_ranges,
+                                    sizeof(*submap), GFP_KERNEL);
+       if (!submap)
+               return -ENOMEM;
+
+       epf_bar->submap = submap;
+       epf_bar->num_submap = total_ranges;
+       dev_dbg(dev, "Requesting BAR%d layout (#. of subranges is %u):\n",
+               barno, total_ranges);
+
+       for (i = 0; i < mw_cnt; i++) {
+               unsigned int mw = mws[i].mw;
+
+               dev_dbg(dev, "- MW%d\n", 1 + mw);
+               for (j = 0; j < ntb->num_subrange[mw]; j++) {
+                       dev_dbg(dev, "  - addr/size = %#llx/%#llx\n",
+                               ntb->mw_subrange[mw][j].addr,
+                               ntb->mw_subrange[mw][j].size);
+                       submap[cur].phys_addr = ntb->mw_subrange[mw][j].addr;
+                       submap[cur].size = ntb->mw_subrange[mw][j].size;
+                       cur++;
+               }
+       }
+
+       ret = pci_epc_set_bar(ntb->epf->epc, ntb->epf->func_no,
+                             ntb->epf->vfunc_no, epf_bar);
+       if (ret)
+               dev_err(dev, "BAR%d: failed to program mappings for MW%d: %d\n",
+                       barno, idx + 1, ret);
+
+       return ret;
+}
+
+static int vntb_epf_mw_set_trans(struct ntb_dev *ndev, int pidx, int idx,
+                                dma_addr_t addr, resource_size_t size)
+{
+       struct epf_ntb *ntb = ntb_ndev(ndev);
+       struct pci_epf_bar *epf_bar;
+       resource_size_t bar_size;
+       enum pci_barno barno;
        struct device *dev;
+       unsigned int i;
+       int ret;
 
        dev = &ntb->ntb->dev;
        barno = ntb->epf_ntb_bar[BAR_MW1 + idx];
        epf_bar = &ntb->epf->bar[barno];
        epf_bar->phys_addr = addr;
        epf_bar->barno = barno;
-       epf_bar->size = size;
 
-       ret = pci_epc_set_bar(ntb->epf->epc, 0, 0, epf_bar);
-       if (ret) {
-               dev_err(dev, "failure set mw trans\n");
-               return ret;
+       bar_size = epf_bar->size;
+       if (!bar_size || !size)
+               return -EINVAL;
+
+       if (size != ntb->mws_size[idx])
+               return -EINVAL;
+
+       /*
+        * Even if the caller intends to map the entire MW, the MW might
+        * actually be just a part of the BAR. In that case, redirect the
+        * handling to vntb_epf_mw_set_trans_ranges().
+        */
+       if (size < bar_size) {
+               struct ntb_mw_subrange r = {
+                       .addr = addr,
+                       .size = size,
+               };
+               return vntb_epf_mw_set_trans_ranges(ndev, pidx, idx, 1, &r);
        }
-       return 0;
+
+       /* Drop any stale cache for the BAR. */
+       for (i = 0; i < MAX_MW; i++) {
+               if (ntb->epf_ntb_bar[BAR_MW1 + i] != barno)
+                       continue;
+               devm_kfree(&ntb->epf->dev, ntb->mw_subrange[i]);
+               ntb->mw_subrange[i] = NULL;
+               ntb->num_subrange[i] = 0;
+       }
+
+       /* Not use subrange mapping. If it's used in the past, clear it off. */
+       devm_kfree(&ntb->epf->dev, epf_bar->submap);
+       epf_bar->submap = NULL;
+       epf_bar->num_submap = 0;
+
+       ret = pci_epc_set_bar(ntb->epf->epc, ntb->epf->func_no,
+                             ntb->epf->vfunc_no, epf_bar);
+       if (ret)
+               dev_err(dev, "failure set mw trans\n");
+
+       return ret;
 }
 
 static int vntb_epf_mw_clear_trans(struct ntb_dev *ntb, int pidx, int idx)
@@ -1590,6 +1756,7 @@ static const struct ntb_dev_ops vntb_epf_ops = {
        .db_vector_mask         = vntb_epf_db_vector_mask,
        .db_set_mask            = vntb_epf_db_set_mask,
        .mw_set_trans           = vntb_epf_mw_set_trans,
+       .mw_set_trans_ranges    = vntb_epf_mw_set_trans_ranges,
        .mw_clear_trans         = vntb_epf_mw_clear_trans,
        .peer_mw_get_addr       = vntb_epf_peer_mw_get_addr,
        .link_enable            = vntb_epf_link_enable,
-- 
2.51.0


Reply via email to