Date:   Sun, 21 Jul 2019 00:55:48 +0200
From:   Helge Deller <deller@gmx.de>
To:     linux-parisc@vger.kernel.org,
        James Bottomley <James.Bottomley@hansenpartnership.com>,
        John David Anglin <dave.anglin@bell.net>
Subject: [PATCH] parisc: Flush ITLB in flush_tlb_all_local() only on split
 TLB machines
Message-ID: <20190720225548.GA15055@ls3530.fritz.box>
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flush_tlb_all_local() flushes the ITLB and DTLB of the CPU.
In case the machine does not have separate ITLBs and DTLBs, use the
alternative functionality to replace the code which flushes the ITLB
with nops while keeping the code which flushes the DTLB.

Signed-off-by: Helge Deller <deller@gmx.de>

diff --git a/arch/parisc/kernel/pacache.S b/arch/parisc/kernel/pacache.S
index ba67893a1d72..df46b0e5a915 100644
=2D-- a/arch/parisc/kernel/pacache.S
+++ b/arch/parisc/kernel/pacache.S
@@ -63,7 +63,7 @@ ENTRY_CFI(flush_tlb_all_local)

 	/* Flush Instruction Tlb */

-	LDREG		ITLB_SID_BASE(%r1), %r20
+88:	LDREG		ITLB_SID_BASE(%r1), %r20
 	LDREG		ITLB_SID_STRIDE(%r1), %r21
 	LDREG		ITLB_SID_COUNT(%r1), %r22
 	LDREG		ITLB_OFF_BASE(%r1), %arg0
@@ -103,6 +103,7 @@ fitonemiddle:					/* Loop if LOOP =3D 1 */
 	add		%r21, %r20, %r20		/* increment space */

 fitdone:
+	ALTERNATIVE(88b, fitdone, ALT_COND_NO_SPLIT_TLB, INSN_NOP)

 	/* Flush Data Tlb */