Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1230628

[PATCH 10/10] MIPS: CM,CPC: ensure core-other GCRs reflect the correct core

Show all headers | View raw

Ensure the update to which core the core-other GCR regions reflect has
taken place before any core-other GCRs are accessed by placing a memory
barrier (sync instruction) between the write to the core-other registers
and any such GCR accesses.

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

 arch/mips/kernel/mips-cm.c  | 6 ++++++
 arch/mips/kernel/mips-cpc.c | 6 ++++++
 2 files changed, 12 insertions(+)

diff --git a/arch/mips/kernel/mips-cm.c b/arch/mips/kernel/mips-cm.c
index fef2647..485e441 100644
--- a/arch/mips/kernel/mips-cm.c
+++ b/arch/mips/kernel/mips-cm.c
@@ -278,6 +278,12 @@ void mips_cm_lock_other(unsigned int core, unsigned int vp)
 	}
 
 	write_gcr_cl_other(val);
+
+	/*
+	 * Ensure the core-other region reflects the appropriate core &
+	 * VP before any accesses to it occur.
+	 */
+	mb();
 }
 
 void mips_cm_unlock_other(void)
diff --git a/arch/mips/kernel/mips-cpc.c b/arch/mips/kernel/mips-cpc.c
index 8af4d62..566b8d2 100644
--- a/arch/mips/kernel/mips-cpc.c
+++ b/arch/mips/kernel/mips-cpc.c
@@ -76,6 +76,12 @@ void mips_cpc_lock_other(unsigned int core)
 	spin_lock_irqsave(&per_cpu(cpc_core_lock, curr_core),
 			  per_cpu(cpc_core_lock_flags, curr_core));
 	write_cpc_cl_other(core << CPC_Cx_OTHER_CORENUM_SHF);
+
+	/*
+	 * Ensure the core-other region reflects the appropriate core &
+	 * VP before any accesses to it occur.
+	 */
+	mb();
 }
 
 void mips_cpc_unlock_other(void)
-- 
2.5.3

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Back to linux.kernel | Previous | Next | Find similar | Unroll thread

Thread

[PATCH 10/10] MIPS: CM,CPC: ensure core-other GCRs reflect the correct core Paul Burton <paul.burton@imgtec.com> - 2015-09-22 20:20 +0200

csiph-web