[PATCH v2 2/3] MIPS: print MAAR configuration during boot

From: Paul Burton
Date: Fri Sep 25 2015 - 12:00:41 EST


Verifying that the MAAR configuration is as expected is useful when
debugging the performance of a system. Print out the memory regions
configured via MAAR along with their attributes.

Signed-off-by: Paul Burton <paul.burton@xxxxxxxxxx>
---

Changes in v2: None

arch/mips/mm/init.c | 29 +++++++++++++++++++++++++++++
1 file changed, 29 insertions(+)

diff --git a/arch/mips/mm/init.c b/arch/mips/mm/init.c
index 074ac54..023c164 100644
--- a/arch/mips/mm/init.c
+++ b/arch/mips/mm/init.c
@@ -291,6 +291,7 @@ unsigned __weak platform_maar_init(unsigned num_pairs)
static void maar_init(void)
{
unsigned num_maars, used, i;
+ phys_addr_t lower, upper, attr;

if (!cpu_has_maar)
return;
@@ -313,6 +314,34 @@ static void maar_init(void)
write_c0_maar(0);
back_to_back_c0_hazard();
}
+
+ pr_info("MAAR configuration:\n");
+ for (i = 0; i < num_maars; i += 2) {
+ write_c0_maari(i);
+ back_to_back_c0_hazard();
+ upper = read_c0_maar();
+
+ write_c0_maari(i + 1);
+ back_to_back_c0_hazard();
+ lower = read_c0_maar();
+
+ attr = lower & upper;
+ lower = (lower & MIPS_MAAR_ADDR) << 4;
+ upper = ((upper & MIPS_MAAR_ADDR) << 4) | 0xffff;
+
+ pr_info(" [%d]: ", i / 2);
+ if (!(attr & MIPS_MAAR_V)) {
+ pr_cont("disabled\n");
+ continue;
+ }
+
+ pr_cont("%pa-%pa", &lower, &upper);
+
+ if (attr & MIPS_MAAR_S)
+ pr_cont(" speculate");
+
+ pr_cont("\n");
+ }
}

#ifndef CONFIG_NEED_MULTIPLE_NODES
--
2.5.3

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