Merge tag 'renesas-boards-cleanups2-for-v3.19' of git://git.kernel.org/pub/scm/linux...

[firefly-linux-kernel-4.4.55.git] / drivers / misc / cxl / fault.c

diff --git a/drivers/misc/cxl/fault.c b/drivers/misc/cxl/fault.c
index d0e97fd3d4c5fc7d2527a0ccb3b794bd7666e6b2..c99e896604ee35909e0a2d55bbd95fd31caddbea 100644 (file)
--- a/drivers/misc/cxl/fault.c
+++ b/drivers/misc/cxl/fault.c
@@ -21,46 +21,64 @@
 
 #include "cxl.h"
 
-static struct cxl_sste* find_free_sste(struct cxl_sste *primary_group,
-                                      unsigned int *lru)
+static bool sste_matches(struct cxl_sste *sste, struct copro_slb *slb)
 {
+       return ((sste->vsid_data == cpu_to_be64(slb->vsid)) &&
+               (sste->esid_data == cpu_to_be64(slb->esid)));
+}
+
+/*
+ * This finds a free SSTE for the given SLB, or returns NULL if it's already in
+ * the segment table.
+ */
+static struct cxl_sste* find_free_sste(struct cxl_context *ctx,
+                                      struct copro_slb *slb)
+{
+       struct cxl_sste *primary, *sste, *ret = NULL;
+       unsigned int mask = (ctx->sst_size >> 7) - 1; /* SSTP0[SegTableSize] */
        unsigned int entry;
-       struct cxl_sste *sste, *group = primary_group;
+       unsigned int hash;
+
+       if (slb->vsid & SLB_VSID_B_1T)
+               hash = (slb->esid >> SID_SHIFT_1T) & mask;
+       else /* 256M */
+               hash = (slb->esid >> SID_SHIFT) & mask;
+
+       primary = ctx->sstp + (hash << 3);
 
-       for (entry = 0; entry < 8; entry++) {
-               sste = group + entry;
-               if (!(be64_to_cpu(sste->esid_data) & SLB_ESID_V))
-                       return sste;
+       for (entry = 0, sste = primary; entry < 8; entry++, sste++) {
+               if (!ret && !(be64_to_cpu(sste->esid_data) & SLB_ESID_V))
+                       ret = sste;
+               if (sste_matches(sste, slb))
+                       return NULL;
        }
+       if (ret)
+               return ret;
+
        /* Nothing free, select an entry to cast out */
-       sste = primary_group + *lru;
-       *lru = (*lru + 1) & 0x7;
+       ret = primary + ctx->sst_lru;
+       ctx->sst_lru = (ctx->sst_lru + 1) & 0x7;
 
-       return sste;
+       return ret;
 }
 
 static void cxl_load_segment(struct cxl_context *ctx, struct copro_slb *slb)
 {
        /* mask is the group index, we search primary and secondary here. */
-       unsigned int mask = (ctx->sst_size >> 7)-1; /* SSTP0[SegTableSize] */
        struct cxl_sste *sste;
-       unsigned int hash;
        unsigned long flags;
 
-
-       if (slb->vsid & SLB_VSID_B_1T)
-               hash = (slb->esid >> SID_SHIFT_1T) & mask;
-       else /* 256M */
-               hash = (slb->esid >> SID_SHIFT) & mask;
-
        spin_lock_irqsave(&ctx->sste_lock, flags);
-       sste = find_free_sste(ctx->sstp + (hash << 3), &ctx->sst_lru);
+       sste = find_free_sste(ctx, slb);
+       if (!sste)
+               goto out_unlock;
 
        pr_devel("CXL Populating SST[%li]: %#llx %#llx\n",
                        sste - ctx->sstp, slb->vsid, slb->esid);
 
        sste->vsid_data = cpu_to_be64(slb->vsid);
        sste->esid_data = cpu_to_be64(slb->esid);
+out_unlock:
        spin_unlock_irqrestore(&ctx->sste_lock, flags);
 }