powerpc/powernv: Check device-tree for RFI flush settings

New device-tree properties are available which tell the hypervisor
settings related to the RFI flush. Use them to determine the
appropriate flush instruction to use, and whether the flush is
required.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

diff --git a/arch/powerpc/platforms/powernv/setup.c b/arch/powerpc/platforms/powernv/setup.c
index 1edfbc1e40f4387b30dd5c0a9491935460feaf92..4fb21e17504aad72295a9e1cdffe54c5547379bd 100644 (file)
--- a/arch/powerpc/platforms/powernv/setup.c
+++ b/arch/powerpc/platforms/powernv/setup.c
@@ -37,13 +37,62 @@
 #include <asm/kexec.h>
 #include <asm/smp.h>
 #include <asm/tm.h>
+#include <asm/setup.h>
 
 #include "powernv.h"
 
+static void pnv_setup_rfi_flush(void)
+{
+       struct device_node *np, *fw_features;
+       enum l1d_flush_type type;
+       int enable;
+
+       /* Default to fallback in case fw-features are not available */
+       type = L1D_FLUSH_FALLBACK;
+       enable = 1;
+
+       np = of_find_node_by_name(NULL, "ibm,opal");
+       fw_features = of_get_child_by_name(np, "fw-features");
+       of_node_put(np);
+
+       if (fw_features) {
+               np = of_get_child_by_name(fw_features, "inst-l1d-flush-trig2");
+               if (np && of_property_read_bool(np, "enabled"))
+                       type = L1D_FLUSH_MTTRIG;
+
+               of_node_put(np);
+
+               np = of_get_child_by_name(fw_features, "inst-l1d-flush-ori30,30,0");
+               if (np && of_property_read_bool(np, "enabled"))
+                       type = L1D_FLUSH_ORI;
+
+               of_node_put(np);
+
+               /* Enable unless firmware says NOT to */
+               enable = 2;
+               np = of_get_child_by_name(fw_features, "needs-l1d-flush-msr-hv-1-to-0");
+               if (np && of_property_read_bool(np, "disabled"))
+                       enable--;
+
+               of_node_put(np);
+
+               np = of_get_child_by_name(fw_features, "needs-l1d-flush-msr-pr-0-to-1");
+               if (np && of_property_read_bool(np, "disabled"))
+                       enable--;
+
+               of_node_put(np);
+               of_node_put(fw_features);
+       }
+
+       setup_rfi_flush(type, enable > 0);
+}
+
 static void __init pnv_setup_arch(void)
 {
        set_arch_panic_timeout(10, ARCH_PANIC_TIMEOUT);
 
+       pnv_setup_rfi_flush();
+
        /* Initialize SMP */
        pnv_smp_init();