arch/tile: parameterize system PLs to support KVM port
While not a port to KVM (yet), this change modifies the kernel
to be able to build either at PL1 or at PL2 with a suitable
config switch. Pushing up this change avoids handling branch
merge issues going forward with the KVM work.
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
diff --git a/arch/tile/kernel/process.c b/arch/tile/kernel/process.c
index 221f12b..8430f45 100644
--- a/arch/tile/kernel/process.c
+++ b/arch/tile/kernel/process.c
@@ -305,15 +305,25 @@
/* Allow user processes to access the DMA SPRs */
void grant_dma_mpls(void)
{
+#if CONFIG_KERNEL_PL == 2
+ __insn_mtspr(SPR_MPL_DMA_CPL_SET_1, 1);
+ __insn_mtspr(SPR_MPL_DMA_NOTIFY_SET_1, 1);
+#else
__insn_mtspr(SPR_MPL_DMA_CPL_SET_0, 1);
__insn_mtspr(SPR_MPL_DMA_NOTIFY_SET_0, 1);
+#endif
}
/* Forbid user processes from accessing the DMA SPRs */
void restrict_dma_mpls(void)
{
+#if CONFIG_KERNEL_PL == 2
+ __insn_mtspr(SPR_MPL_DMA_CPL_SET_2, 1);
+ __insn_mtspr(SPR_MPL_DMA_NOTIFY_SET_2, 1);
+#else
__insn_mtspr(SPR_MPL_DMA_CPL_SET_1, 1);
__insn_mtspr(SPR_MPL_DMA_NOTIFY_SET_1, 1);
+#endif
}
/* Pause the DMA engine, then save off its state registers. */
@@ -524,7 +534,7 @@
* Switch kernel SP, PC, and callee-saved registers.
* In the context of the new task, return the old task pointer
* (i.e. the task that actually called __switch_to).
- * Pass the value to use for SYSTEM_SAVE_1_0 when we reset our sp.
+ * Pass the value to use for SYSTEM_SAVE_K_0 when we reset our sp.
*/
return __switch_to(prev, next, next_current_ksp0(next));
}