+static void __spu_kernel_slb(void *addr, struct spu_slb *slb)
+{
+ unsigned long ea = (unsigned long)addr;
+ u64 llp;
+
+ if (REGION_ID(ea) == KERNEL_REGION_ID)
+ llp = mmu_psize_defs[mmu_linear_psize].sllp;
+ else
+ llp = mmu_psize_defs[mmu_virtual_psize].sllp;
+
+ slb->vsid = (get_kernel_vsid(ea, MMU_SEGSIZE_256M) << SLB_VSID_SHIFT) |
+ SLB_VSID_KERNEL | llp;
+ slb->esid = (ea & ESID_MASK) | SLB_ESID_V;
+}
+
+/**
+ * Given an array of @nr_slbs SLB entries, @slbs, return non-zero if the
+ * address @new_addr is present.
+ */
+static inline int __slb_present(struct spu_slb *slbs, int nr_slbs,
+ void *new_addr)
+{
+ unsigned long ea = (unsigned long)new_addr;
+ int i;
+
+ for (i = 0; i < nr_slbs; i++)
+ if (!((slbs[i].esid ^ ea) & ESID_MASK))
+ return 1;
+
+ return 0;
+}
+
+/**
+ * Setup the SPU kernel SLBs, in preparation for a context save/restore. We
+ * need to map both the context save area, and the save/restore code.
+ *
+ * Because the lscsa and code may cross segment boundaires, we check to see
+ * if mappings are required for the start and end of each range. We currently
+ * assume that the mappings are smaller that one segment - if not, something
+ * is seriously wrong.
+ */
+void spu_setup_kernel_slbs(struct spu *spu, struct spu_lscsa *lscsa,
+ void *code, int code_size)
+{
+ struct spu_slb slbs[4];
+ int i, nr_slbs = 0;
+ /* start and end addresses of both mappings */
+ void *addrs[] = {
+ lscsa, (void *)lscsa + sizeof(*lscsa) - 1,
+ code, code + code_size - 1
+ };
+
+ /* check the set of addresses, and create a new entry in the slbs array
+ * if there isn't already a SLB for that address */
+ for (i = 0; i < ARRAY_SIZE(addrs); i++) {
+ if (__slb_present(slbs, nr_slbs, addrs[i]))
+ continue;
+
+ __spu_kernel_slb(addrs[i], &slbs[nr_slbs]);
+ nr_slbs++;
+ }
+
+ /* Add the set of SLBs */
+ for (i = 0; i < nr_slbs; i++)
+ spu_load_slb(spu, i, &slbs[i]);
+}
+EXPORT_SYMBOL_GPL(spu_setup_kernel_slbs);
+