ppc/85xx: Make SPD DDR TLB setup code use dynamic entry allocation

Now that we track which TLB CAM entries are used we can allocate
entries on the fly.  Change the SPD DDR TLB setup code to assume
we use at most 8 TLBs (or the number free, which ever is fewer).

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

cpu/mpc85xx/tlb.c

@@ -227,14 +227,10 @@ void init_addr_map(void)
 }
 #endif
 
-#ifndef CONFIG_SYS_DDR_TLB_START
-#define CONFIG_SYS_DDR_TLB_START 8
-#endif
-
 unsigned int setup_ddr_tlbs(unsigned int memsize_in_meg)
 {
+	int i;
 	unsigned int tlb_size;
-	unsigned int ram_tlb_index = CONFIG_SYS_DDR_TLB_START;
 	unsigned int ram_tlb_address = (unsigned int)CONFIG_SYS_DDR_SDRAM_BASE;
 	unsigned int max_cam = (mfspr(SPRN_TLB1CFG) >> 16) & 0xf;
 	u64 size, memsize = (u64)memsize_in_meg << 20;
@@ -244,10 +240,14 @@ unsigned int setup_ddr_tlbs(unsigned int memsize_in_meg)
 	/* Convert (4^max) kB to (2^max) bytes */
 	max_cam = max_cam * 2 + 10;
 
-	for (; size && ram_tlb_index < 16; ram_tlb_index++) {
+	for (i = 0; size && i < 8; i++) {
+		int ram_tlb_index = find_free_tlbcam();
 		u32 camsize = __ilog2_u64(size) & ~1U;
 		u32 align = __ilog2(ram_tlb_address) & ~1U;
 
+		if (ram_tlb_index == -1)
+			break;
+
 		if (align == -2) align = max_cam;
 		if (camsize > align)
 			camsize = align;