X-Git-Url: http://git.cascardo.eti.br/?a=blobdiff_plain;f=arch%2Farm64%2Fkernel%2Fhead.S;h=917d98108b3f05d9b1013020f9f576a3db776bc6;hb=fe26e52712ccab6648df17ecc029a68a69a01a85;hp=ffe9c2b6431bd5c0cb1e9982afe84e13a82e2043;hpb=9638685e32af961943b679fcb72d4ddd458eb18f;p=cascardo%2Flinux.git

diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
index ffe9c2b6431b..917d98108b3f 100644
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S
@@ -514,9 +514,14 @@ CPU_LE(	movk	x0, #0x30d0, lsl #16	)	// Clear EE and E0E on LE systems
 #endif
 
 	/* EL2 debug */
+	mrs	x0, id_aa64dfr0_el1		// Check ID_AA64DFR0_EL1 PMUVer
+	sbfx	x0, x0, #8, #4
+	cmp	x0, #1
+	b.lt	4f				// Skip if no PMU present
 	mrs	x0, pmcr_el0			// Disable debug access traps
 	ubfx	x0, x0, #11, #5			// to EL2 and allow access to
 	msr	mdcr_el2, x0			// all PMU counters from EL1
+4:
 
 	/* Stage-2 translation */
 	msr	vttbr_el2, xzr