arm64/boot: Disable trapping of PMZR_EL0 writes to EL2grafted

__init_el2_fgt2() writes one mask to both HDFGRTR2_EL2 and HDFGWTR2_EL2.
PMZR_EL0 is write-only, so its trap bit, nPMZR_EL0, exists only in
HDFGWTR2_EL2 and is therefore never set: a PMZR_EL0 write from the host
traps to EL2, where the nVHE hypervisor has no handler and BUG()s. The
kernel never writes PMZR_EL0, but kernel.perf_user_access=1 has the PMU
driver set PMUSERENR_EL0.UEN for a task with a user-read event, so a
write from EL0 reaches the trap and takes the host down without a panic
message.

Accumulate the HDFGWTR2_EL2 bits separately, as __init_el2_fgt() already
does for HDFGWTR_EL2, and set nPMZR_EL0 with the other FEAT_PMUv3p9
bits.

Fixes: 858c7bfcb35e1 ("arm64/boot: Enable EL2 requirements for FEAT_PMUv3p9")
Cc: stable@vger.kernel.org
Signed-off-by: Fuad Tabba <fuad.tabba@linux.dev>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Oliver Upton <oupton@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>

1 files changed, 51 insertions, 0 deletions

diff --git a/include/video/hecubafb.h b/include/video/hecubafb.h
new file mode 100644
index 000000000..7b9952339
--- /dev/null
+++ b/include/video/hecubafb.h
@@ -0,0 +1,51 @@
+/*
+ * hecubafb.h - definitions for the hecuba framebuffer driver
+ *
+ * Copyright (C) 2008 by Jaya Kumar
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file COPYING in the main directory of this archive for
+ * more details.
+ *
+ */
+
+#ifndef _LINUX_HECUBAFB_H_
+#define _LINUX_HECUBAFB_H_
+
+/* Apollo controller specific defines */
+#define APOLLO_START_NEW_IMG	0xA0
+#define APOLLO_STOP_IMG_DATA	0xA1
+#define APOLLO_DISPLAY_IMG	0xA2
+#define APOLLO_ERASE_DISPLAY	0xA3
+#define APOLLO_INIT_DISPLAY	0xA4
+
+/* Hecuba interface specific defines */
+#define HCB_WUP_BIT	0x01
+#define HCB_DS_BIT 	0x02
+#define HCB_RW_BIT 	0x04
+#define HCB_CD_BIT 	0x08
+#define HCB_ACK_BIT 	0x80
+
+/* struct used by hecuba. board specific stuff comes from *board */
+struct hecubafb_par {
+	struct fb_info *info;
+	struct hecuba_board *board;
+	void (*send_command)(struct hecubafb_par *, unsigned char);
+	void (*send_data)(struct hecubafb_par *, unsigned char);
+};
+
+/* board specific routines
+board drivers can implement wait_for_ack with interrupts if desired. if
+wait_for_ack is called with clear=0, then go to sleep and return when ack
+goes hi or if wait_for_ack with clear=1, then return when ack goes lo */
+struct hecuba_board {
+	struct module *owner;
+	void (*remove)(struct hecubafb_par *);
+	void (*set_ctl)(struct hecubafb_par *, unsigned char, unsigned char);
+	void (*set_data)(struct hecubafb_par *, unsigned char);
+	void (*wait_for_ack)(struct hecubafb_par *, int);
+	int (*init)(struct hecubafb_par *);
+};
+
+
+#endif