irqchip, gicv3-its: Workaround for Cavium ThunderX errata 22375, 24313

This implements two gicv3-its errata workarounds for ThunderX. Both
with small impact affecting only ITS table allocation.

 erratum 22375: only alloc 8MB table size
 erratum 24313: ignore memory access type

The fixes are in ITS initialization and basically ignore memory access
type and table size provided by the TYPER and BASER registers.

v3:
 * fix erratum to be dependend from iidr

Signed-off-by: Robert Richter <rrichter@cavium.com>
Signed-off-by: Vadim Lomovtsev <Vadim.Lomovtsev@caviumnetworks.com>

diff --git a/drivers/irqchip/irq-gic-v3-its.c b/drivers/irqchip/irq-gic-v3-its.c
index 0f15ee6ec677f4ea5beed243a8d85f10b8b22da6..6f80ec4f0a87a1e8774d3d99356b84a9ee3ad21a 100644 (file)
--- a/drivers/irqchip/irq-gic-v3-its.c
+++ b/drivers/irqchip/irq-gic-v3-its.c
@@ -39,7 +39,8 @@
 #include "irq-gic-common.h"
 #include "irqchip.h"
 
-#define ITS_FLAGS_CMDQ_NEEDS_FLUSHING          (1 << 0)
+#define ITS_FLAGS_CMDQ_NEEDS_FLUSHING          (1ULL << 0)
+#define ITS_FLAGS_CAVIUM_THUNDERX              (1ULL << 1)
 
 #define RDIST_FLAGS_PROPBASE_NEEDS_FLUSHING    (1 << 0)
 
@@ -838,9 +839,22 @@ static int its_alloc_tables(struct its_node *its)
        int i;
        int psz = SZ_64K;
        u64 shr = GITS_BASER_InnerShareable;
-       u64 cache = GITS_BASER_WaWb;
-       u64 typer = readq_relaxed(its->base + GITS_TYPER);
-       u32 ids = GITS_TYPER_DEVBITS(typer);
+       u64 cache;
+       u64 typer;
+       u32 ids;
+
+       if (its->flags & ITS_FLAGS_CAVIUM_THUNDERX) {
+               /*
+                * erratum 22375: only alloc 8MB table size
+                * erratum 24313: ignore memory access type
+                */
+               cache   = 0;
+               ids     = 0x14;                 /* 20 bits, 8MB */
+       } else {
+               cache   = GITS_BASER_WaWb;
+               typer   = readq_relaxed(its->base + GITS_TYPER);
+               ids     = GITS_TYPER_DEVBITS(typer);
+       }
 
        for (i = 0; i < GITS_BASER_NR_REGS; i++) {
                u64 val = readq_relaxed(its->base + GITS_BASER + i * 8);
@@ -1430,7 +1444,20 @@ static int its_force_quiescent(void __iomem *base)
        }
 }
 
+static void its_enable_cavium_thunderx(void *data)
+{
+       struct its_node *its = data;
+
+       its->flags |= ITS_FLAGS_CAVIUM_THUNDERX;
+}
+
 static const struct gic_capabilities its_errata[] = {
+       {
+               .desc   = "ITS: Cavium errata 22375, 24313",
+               .iidr   = 0xa100034c,   /* ThunderX pass 1.x */
+               .mask   = 0xffff0fff,
+               .init   = its_enable_cavium_thunderx,
+       },
        {
        }
 };