git: 570fae59a8bf - stable/14 - arm64: Support counter access with E2H

From: Andrew Turner <andrew_at_FreeBSD.org>
Date: Mon, 02 Sep 2024 08:50:44 UTC
The branch stable/14 has been updated by andrew:

URL: https://cgit.FreeBSD.org/src/commit/?id=570fae59a8bf9ded19c4de9bf001ee0fa2cf7229

commit 570fae59a8bf9ded19c4de9bf001ee0fa2cf7229
Author:     Andrew Turner <andrew@FreeBSD.org>
AuthorDate: 2024-07-23 09:18:00 +0000
Commit:     Andrew Turner <andrew@FreeBSD.org>
CommitDate: 2024-09-02 08:48:25 +0000

    arm64: Support counter access with E2H
    
    When entering the kernel with the E2H field set the layout of the
    cnthctl_el2 register changes. Use the correct field locations to enable
    access to the counter and timer registers from EL1.
    
    Sponsored by:   Arm Ltd
    Differential Revision:  https://reviews.freebsd.org/D45529
    
    (cherry picked from commit 997511dffe651e1d2d708f37f2ced430a6ab3349)
---
 sys/arm64/arm64/locore.S       | 6 ++++--
 sys/arm64/include/hypervisor.h | 9 +++++++--
 2 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/sys/arm64/arm64/locore.S b/sys/arm64/arm64/locore.S
index 9f3739c85534..e637749b1321 100644
--- a/sys/arm64/arm64/locore.S
+++ b/sys/arm64/arm64/locore.S
@@ -317,8 +317,10 @@ LENTRY(enter_kernel_el)
 	msr	hstr_el2, xzr
 
 	/* Enable access to the physical timers at EL1 */
-	mrs	x2, cnthctl_el2
-	orr	x2, x2, #(CNTHCTL_EL1PCTEN | CNTHCTL_EL1PCEN)
+	tst	x4, #HCR_E2H
+	ldr	x3, =(CNTHCTL_EL1PCTEN | CNTHCTL_EL1PCEN)
+	ldr	x5, =(CNTHCTL_E2H_EL1PCTEN | CNTHCTL_E2H_EL1PTEN)
+	csel	x2, x3, x5, eq
 	msr	cnthctl_el2, x2
 
 	/* Set the counter offset to a known value */
diff --git a/sys/arm64/include/hypervisor.h b/sys/arm64/include/hypervisor.h
index 85ac5cda7037..418047cb22f2 100644
--- a/sys/arm64/include/hypervisor.h
+++ b/sys/arm64/include/hypervisor.h
@@ -37,10 +37,15 @@
 
 /* CNTHCTL_EL2 - Counter-timer Hypervisor Control register */
 #define	CNTHCTL_EVNTI_MASK	(0xf << 4) /* Bit to trigger event stream */
+/* Valid if HCR_EL2.E2H == 0 */
+#define	CNTHCTL_EL1PCTEN	(1 << 0) /* Allow physical counter access */
+#define	CNTHCTL_EL1PCEN		(1 << 1) /* Allow physical timer access */
+/* Valid if HCR_EL2.E2H == 1 */
+#define	CNTHCTL_E2H_EL1PCTEN	(1 << 10) /* Allow physical counter access */
+#define	CNTHCTL_E2H_EL1PTEN	(1 << 11) /* Allow physical timer access */
+/* Unconditionally valid */
 #define	CNTHCTL_EVNTDIR		(1 << 3) /* Control transition trigger bit */
 #define	CNTHCTL_EVNTEN		(1 << 2) /* Enable event stream */
-#define	CNTHCTL_EL1PCEN		(1 << 1) /* Allow EL0/1 physical timer access */
-#define	CNTHCTL_EL1PCTEN	(1 << 0) /*Allow EL0/1 physical counter access*/
 
 /* CPTR_EL2 - Architecture feature trap register */
 /* Valid if HCR_EL2.E2H == 0 */