[POWERPC] bestcomm: Restrict bus prefetch bugfix to original mpc5200 silicon.
Only the MPC5200 needs this bug fix. MPC5200B is okay.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
diff --git a/arch/powerpc/sysdev/bestcomm/bestcomm.c b/arch/powerpc/sysdev/bestcomm/bestcomm.c
index 48492a8..740ad73 100644
--- a/arch/powerpc/sysdev/bestcomm/bestcomm.c
+++ b/arch/powerpc/sysdev/bestcomm/bestcomm.c
@@ -269,6 +269,7 @@
int task;
phys_addr_t tdt_pa, ctx_pa, var_pa, fdt_pa;
unsigned int tdt_size, ctx_size, var_size, fdt_size;
+ u16 regval;
/* Allocate & clear SRAM zones for FDT, TDTs, contexts and vars/incs */
tdt_size = BCOM_MAX_TASKS * sizeof(struct bcom_tdt);
@@ -319,9 +320,11 @@
/* Init 'always' initiator */
out_8(&bcom_eng->regs->ipr[BCOM_INITIATOR_ALWAYS], BCOM_IPR_ALWAYS);
- /* Disable COMM Bus Prefetch, apparently it's not reliable yet */
- /* FIXME: This should be done on 5200 and not 5200B ... */
- out_be16(&bcom_eng->regs->PtdCntrl, in_be16(&bcom_eng->regs->PtdCntrl) | 1);
+ /* Disable COMM Bus Prefetch on the original 5200; it's broken */
+ if ((mfspr(SPRN_SVR) & MPC5200_SVR_MASK) == MPC5200_SVR) {
+ regval = in_be16(&bcom_eng->regs->PtdCntrl);
+ out_be16(&bcom_eng->regs->PtdCntrl, regval | 1);
+ }
/* Init lock */
spin_lock_init(&bcom_eng->lock);