[PARISC] Ensure Space ID hashing is turned off
Check PDC_CACHE to see if spaceid hashing is turned on, and fail to
boot if that is the case.
However, some old machines do not implement the PDC_CACHE_RET_SPID
firmware call, so continue to boot if the call fails because of
PDC_BAD_OPTION (but fail in all other error returns).
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
diff --git a/arch/parisc/kernel/firmware.c b/arch/parisc/kernel/firmware.c
index 0596f27..c80c277 100644
--- a/arch/parisc/kernel/firmware.c
+++ b/arch/parisc/kernel/firmware.c
@@ -512,6 +512,26 @@
return retval;
}
+/**
+ * pdc_spaceid_bits - Return whether Space ID hashing is turned on.
+ * @space_bits: Should be 0, if not, bad mojo!
+ *
+ * Returns information about Space ID hashing.
+ */
+int pdc_spaceid_bits(unsigned long *space_bits)
+{
+ int retval;
+
+ spin_lock_irq(&pdc_lock);
+ pdc_result[0] = 0;
+ retval = mem_pdc_call(PDC_CACHE, PDC_CACHE_RET_SPID, __pa(pdc_result), 0);
+ convert_to_wide(pdc_result);
+ *space_bits = pdc_result[0];
+ spin_unlock_irq(&pdc_lock);
+
+ return retval;
+}
+
#ifndef CONFIG_PA20
/**
* pdc_btlb_info - Return block TLB information.