Most Apple IOPs run a firmware that is based on what Apple calls
RTKit. RTKit implements a common mailbox protocol. This code
provides an implementation of the AP side of this protocol,
providing a function to initialize RTKit-based firmwares as well
as a function to do a clean shutdown of this firmware.
Signed-off-by: Mark Kettenis <kette...@openbsd.org>
---
arch/arm/include/asm/arch-apple/rtkit.h | 11 ++
arch/arm/mach-apple/Makefile | 1 +
arch/arm/mach-apple/rtkit.c | 231 ++++++++++++++++++++++++
3 files changed, 243 insertions(+)
create mode 100644 arch/arm/include/asm/arch-apple/rtkit.h
create mode 100644 arch/arm/mach-apple/rtkit.c
diff --git a/arch/arm/include/asm/arch-apple/rtkit.h
b/arch/arm/include/asm/arch-apple/rtkit.h
new file mode 100644
index 0000000000..51f77f298c
--- /dev/null
+++ b/arch/arm/include/asm/arch-apple/rtkit.h
@@ -0,0 +1,11 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * (C) Copyright 2021 Mark Kettenis <kette...@openbsd.org>
+ */
+
+#define APPLE_RTKIT_PWR_STATE_SLEEP 0x01
+#define APPLE_RTKIT_PWR_STATE_QUIESCED 0x10
+#define APPLE_RTKIT_PWR_STATE_ON 0x20
+
+int apple_rtkit_init(struct mbox_chan *);
+int apple_rtkit_shutdown(struct mbox_chan *, int);
diff --git a/arch/arm/mach-apple/Makefile b/arch/arm/mach-apple/Makefile
index e74a8c9df1..52f30a777b 100644
--- a/arch/arm/mach-apple/Makefile
+++ b/arch/arm/mach-apple/Makefile
@@ -2,3 +2,4 @@
obj-y += board.o
obj-y += lowlevel_init.o
+obj-y += rtkit.o
diff --git a/arch/arm/mach-apple/rtkit.c b/arch/arm/mach-apple/rtkit.c
new file mode 100644
index 0000000000..79048a801f
--- /dev/null
+++ b/arch/arm/mach-apple/rtkit.c
@@ -0,0 +1,231 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * (C) Copyright 2021 Mark Kettenis <kette...@openbsd.org>
+ * (C) Copyright 2021 Copyright The Asahi Linux Contributors
+ */
+
+#include <common.h>
+#include <mailbox.h>
+#include <malloc.h>
+
+#include <asm/arch-apple/rtkit.h>
+#include <linux/apple-mailbox.h>
+#include <linux/bitfield.h>
+
+#define APPLE_RTKIT_EP_MGMT 0
+#define APPLE_RTKIT_EP_CRASHLOG 1
+#define APPLE_RTKIT_EP_SYSLOG 2
+#define APPLE_RTKIT_EP_DEBUG 3
+#define APPLE_RTKIT_EP_IOREPORT 4
+
+/* Messages for management endpoint. */
+#define APPLE_RTKIT_MGMT_TYPE GENMASK(59, 52)
+
+#define APPLE_RTKIT_MGMT_PWR_STATE GENMASK(15, 0)
+
+#define APPLE_RTKIT_MGMT_HELLO 1
+#define APPLE_RTKIT_MGMT_HELLO_REPLY 2
+#define APPLE_RTKIT_MGMT_HELLO_MINVER GENMASK(15, 0)
+#define APPLE_RTKIT_MGMT_HELLO_MAXVER GENMASK(31, 16)
+
+#define APPLE_RTKIT_MGMT_STARTEP 5
+#define APPLE_RTKIT_MGMT_STARTEP_EP GENMASK(39, 32)
+#define APPLE_RTKIT_MGMT_STARTEP_FLAG BIT(1)
+
+#define APPLE_RTKIT_MGMT_SET_IOP_PWR_STATE 6
+#define APPLE_RTKIT_MGMT_SET_IOP_PWR_STATE_ACK 7
+
+#define APPLE_RTKIT_MGMT_EPMAP 8
+#define APPLE_RTKIT_MGMT_EPMAP_LAST BIT(51)
+#define APPLE_RTKIT_MGMT_EPMAP_BASE GENMASK(34, 32)
+#define APPLE_RTKIT_MGMT_EPMAP_BITMAP GENMASK(31, 0)
+
+#define APPLE_RTKIT_MGMT_EPMAP_REPLY 8
+#define APPLE_RTKIT_MGMT_EPMAP_REPLY_MORE BIT(0)
+
+#define APPLE_RTKIT_MIN_SUPPORTED_VERSION 11
+#define APPLE_RTKIT_MAX_SUPPORTED_VERSION 12
+
+/* Messages for internal endpoints. */
+#define APPLE_RTKIT_BUFFER_REQUEST 1
+#define APPLE_RTKIT_BUFFER_REQUEST_SIZE GENMASK(51, 44)
+#define APPLE_RTKIT_BUFFER_REQUEST_IOVA GENMASK(41, 0)
+
+int apple_rtkit_init(struct mbox_chan *chan)
+{
+ struct apple_mbox_msg msg;
+ int endpoints[256];
+ int nendpoints = 0;
+ int endpoint;
+ int min_ver, max_ver, want_ver;
+ int msgtype, pwrstate;
+ u64 reply;
+ u32 bitmap, base;
+ int i, ret;
+
+ /* Wakup the IOP. */
+ msg.msg0 = FIELD_PREP(APPLE_RTKIT_MGMT_TYPE,
APPLE_RTKIT_MGMT_SET_IOP_PWR_STATE) |
+ FIELD_PREP(APPLE_RTKIT_MGMT_PWR_STATE,
APPLE_RTKIT_PWR_STATE_ON);
+ msg.msg1 = APPLE_RTKIT_EP_MGMT;
+ ret = mbox_send(chan, &msg);
+ if (ret < 0)
+ return ret;
+
+ /* Wait for protocol version negotiation message. */
+ ret = mbox_recv(chan, &msg, 10000);
+ if (ret < 0)
+ return ret;
+
+ endpoint = msg.msg1;
+ msgtype = FIELD_GET(APPLE_RTKIT_MGMT_TYPE, msg.msg0);
+ if (endpoint != APPLE_RTKIT_EP_MGMT) {
+ printf("%s: unexpected endpoint %d\n", __func__, endpoint);
+ return -EINVAL;
+ }
+ if (msgtype != APPLE_RTKIT_MGMT_HELLO) {
+ printf("%s: unexpected message type %d\n", __func__, msgtype);
+ return -EINVAL;
+ }
+
+ min_ver = FIELD_GET(APPLE_RTKIT_MGMT_HELLO_MINVER, msg.msg0);
+ max_ver = FIELD_GET(APPLE_RTKIT_MGMT_HELLO_MAXVER, msg.msg0);
+ want_ver = min(APPLE_RTKIT_MAX_SUPPORTED_VERSION, max_ver);
+
+ if (min_ver > APPLE_RTKIT_MAX_SUPPORTED_VERSION) {
+ printf("%s: firmware min version %d is too new\n",
+ __func__, min_ver);
+ return -ENOTSUPP;
+ }
+
+ if (max_ver < APPLE_RTKIT_MIN_SUPPORTED_VERSION) {
+ printf("%s: firmware max version %d is too old\n",
+ __func__, max_ver);
+ return -ENOTSUPP;
+ }
+
+ /* Ack version. */
+ msg.msg0 = FIELD_PREP(APPLE_RTKIT_MGMT_TYPE,
APPLE_RTKIT_MGMT_HELLO_REPLY) |
+ FIELD_PREP(APPLE_RTKIT_MGMT_HELLO_MINVER, want_ver) |
+ FIELD_PREP(APPLE_RTKIT_MGMT_HELLO_MAXVER, want_ver);
+ msg.msg1 = APPLE_RTKIT_EP_MGMT;
+ ret = mbox_send(chan, &msg);
+ if (ret < 0)
+ return ret;
+
+wait_epmap:
+ /* Wait for endpoint map message. */
+ ret = mbox_recv(chan, &msg, 10000);
+ if (ret < 0)
+ return ret;
+
+ endpoint = msg.msg1;
+ msgtype = FIELD_GET(APPLE_RTKIT_MGMT_TYPE, msg.msg0);
+ if (endpoint != APPLE_RTKIT_EP_MGMT) {
+ printf("%s: unexpected endpoint %d\n", __func__, endpoint);
+ return -EINVAL;
+ }
+ if (msgtype != APPLE_RTKIT_MGMT_EPMAP) {
+ printf("%s: unexpected message type %d\n", __func__, msgtype);
+ return -EINVAL;
+ }
+
+ bitmap = FIELD_GET(APPLE_RTKIT_MGMT_EPMAP_BITMAP, msg.msg0);
+ base = FIELD_GET(APPLE_RTKIT_MGMT_EPMAP_BASE, msg.msg0);
+ for (i = 0; i < 32; i++) {
+ if (bitmap & (1U << i))
+ endpoints[nendpoints++] = base * 32 + i;
+ }
+
+ /* Ack endpoint map. */
+ reply = FIELD_PREP(APPLE_RTKIT_MGMT_TYPE, APPLE_RTKIT_MGMT_EPMAP_REPLY)
|
+ FIELD_PREP(APPLE_RTKIT_MGMT_EPMAP_BASE, base);
+ if (msg.msg0 & APPLE_RTKIT_MGMT_EPMAP_LAST)
+ reply |= APPLE_RTKIT_MGMT_EPMAP_LAST;
+ else
+ reply |= APPLE_RTKIT_MGMT_EPMAP_REPLY_MORE;
+ msg.msg0 = reply;
+ msg.msg1 = APPLE_RTKIT_EP_MGMT;
+ ret = mbox_send(chan, &msg);
+ if (ret < 0)
+ return ret;
+
+ if (reply & APPLE_RTKIT_MGMT_EPMAP_REPLY_MORE)
+ goto wait_epmap;
+
+ for (i = 0; i < nendpoints; i++) {
+ /* Don't start the syslog endpoint since we can't
+ easily handle its messages in U-Boot. */
+ if (endpoints[i] == APPLE_RTKIT_EP_SYSLOG)
+ continue;
+
+ /* Request endpoint. */
+ msg.msg0 = FIELD_PREP(APPLE_RTKIT_MGMT_TYPE,
APPLE_RTKIT_MGMT_STARTEP) |
+ FIELD_PREP(APPLE_RTKIT_MGMT_STARTEP_EP, endpoints[i]) |
+ APPLE_RTKIT_MGMT_STARTEP_FLAG;
+ msg.msg1 = APPLE_RTKIT_EP_MGMT;
+ ret = mbox_send(chan, &msg);
+ if (ret < 0)
+ return ret;
+ }
+
+ pwrstate = APPLE_RTKIT_PWR_STATE_SLEEP;
+ while (pwrstate != APPLE_RTKIT_PWR_STATE_ON) {
+ ret = mbox_recv(chan, &msg, 100000);
+ if (ret < 0)
+ return ret;
+
+ endpoint = msg.msg1;
+ msgtype = FIELD_GET(APPLE_RTKIT_MGMT_TYPE, msg.msg0);
+
+ if (endpoint == APPLE_RTKIT_EP_CRASHLOG ||
+ endpoint == APPLE_RTKIT_EP_SYSLOG ||
+ endpoint == APPLE_RTKIT_EP_IOREPORT) {
+ u64 addr = FIELD_GET(APPLE_RTKIT_BUFFER_REQUEST_IOVA,
msg.msg0);
+ u64 size = FIELD_GET(APPLE_RTKIT_BUFFER_REQUEST_SIZE,
msg.msg0);
+
+ if (msgtype == APPLE_RTKIT_BUFFER_REQUEST && addr != 0)
+ continue;
+
+ msg.msg0 = FIELD_PREP(APPLE_RTKIT_MGMT_TYPE,
APPLE_RTKIT_BUFFER_REQUEST) |
+ FIELD_PREP(APPLE_RTKIT_BUFFER_REQUEST_SIZE,
size) |
+ FIELD_PREP(APPLE_RTKIT_BUFFER_REQUEST_IOVA,
addr);
+ msg.msg1 = endpoint;
+ ret = mbox_send(chan, &msg);
+ if (ret < 0)
+ return ret;
+ continue;
+ }
+
+ if (endpoint != APPLE_RTKIT_EP_MGMT) {
+ printf("%s: unexpected endpoint %d\n", __func__,
endpoint);
+ return -EINVAL;
+ }
+ if (msgtype != APPLE_RTKIT_MGMT_SET_IOP_PWR_STATE_ACK) {
+ printf("%s: unexpected message type %d\n", __func__,
msgtype);
+ return -EINVAL;
+ }
+
+ pwrstate = FIELD_GET(APPLE_RTKIT_MGMT_PWR_STATE, msg.msg0);
+ }
+
+ return 0;
+}
+
+int apple_rtkit_shutdown(struct mbox_chan *chan, int pwrstate)
+{
+ struct apple_mbox_msg msg;
+ int ret;
+
+ msg.msg0 = FIELD_PREP(APPLE_RTKIT_MGMT_TYPE,
APPLE_RTKIT_MGMT_SET_IOP_PWR_STATE) |
+ FIELD_PREP(APPLE_RTKIT_MGMT_PWR_STATE, pwrstate);
+ msg.msg1 = APPLE_RTKIT_EP_MGMT;
+ ret = mbox_send(chan, &msg);
+ if (ret < 0)
+ return ret;
+
+ ret = mbox_recv(chan, &msg, 100000);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
--
2.34.1
