git: 601baffb0b54 - stable/14 - riscv: Create a newbus device for the SBI driver

The branch stable/14 has been updated by jrtc27:

URL: https://cgit.FreeBSD.org/src/commit/?id=601baffb0b54b8fe70ad1dd9fd923fe38d08337e

commit 601baffb0b54b8fe70ad1dd9fd923fe38d08337e
Author:     Jessica Clarke <jrtc27@FreeBSD.org>
AuthorDate: 2024-01-24 23:49:54 +0000
Commit:     Jessica Clarke <jrtc27@FreeBSD.org>
CommitDate: 2024-09-06 23:59:12 +0000

    riscv: Create a newbus device for the SBI driver
    
    This approach is based on the Arm PSCI driver, though that makes more
    extensive use of its softc than we do here. This will be used to extract
    the SBI IPI code as a real PIC.
    
    Reviewed by:    mhorne, imp
    MFC after:      1 month
    Differential Revision:  https://reviews.freebsd.org/D35900
    
    (cherry picked from commit c55272fdf8570b4e15112009ad0066ed156f21a7)
---
 sys/riscv/include/sbi.h |  6 +----
 sys/riscv/riscv/sbi.c   | 65 +++++++++++++++++++++++++++++++++++++++++++------
 2 files changed, 59 insertions(+), 12 deletions(-)

diff --git a/sys/riscv/include/sbi.h b/sys/riscv/include/sbi.h
index 4fbdd598ec4d..bd3991e0a89f 100644
--- a/sys/riscv/include/sbi.h
+++ b/sys/riscv/include/sbi.h
@@ -159,11 +159,7 @@ sbi_call(uint64_t arg7, uint64_t arg6, uint64_t arg0, uint64_t arg1,
 	return (ret);
 }
 
-/* Base extension functions and variables. */
-extern u_long sbi_spec_version;
-extern u_long sbi_impl_id;
-extern u_long sbi_impl_version;
-
+/* Base extension functions. */
 static __inline long
 sbi_probe_extension(long id)
 {
diff --git a/sys/riscv/riscv/sbi.c b/sys/riscv/riscv/sbi.c
index 36aaa8a6ffed..284b29af77df 100644
--- a/sys/riscv/riscv/sbi.c
+++ b/sys/riscv/riscv/sbi.c
@@ -2,6 +2,7 @@
  * SPDX-License-Identifier: BSD-2-Clause
  *
  * Copyright (c) 2019 Mitchell Horne <mhorne@FreeBSD.org>
+ * Copyright (c) 2021 Jessica Clarke <jrtc27@FreeBSD.org>
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -27,10 +28,11 @@
 
 #include <sys/cdefs.h>
 #include <sys/param.h>
-#include <sys/kernel.h>
 #include <sys/systm.h>
-#include <sys/types.h>
+#include <sys/bus.h>
 #include <sys/eventhandler.h>
+#include <sys/kernel.h>
+#include <sys/module.h>
 #include <sys/reboot.h>
 
 #include <machine/md_var.h>
@@ -40,9 +42,15 @@
 #define	OPENSBI_VERSION_MAJOR_OFFSET	16
 #define	OPENSBI_VERSION_MINOR_MASK	0xFFFF
 
-u_long sbi_spec_version;
-u_long sbi_impl_id;
-u_long sbi_impl_version;
+struct sbi_softc {
+	device_t		dev;
+};
+
+static struct sbi_softc *sbi_softc = NULL;
+
+static u_long sbi_spec_version;
+static u_long sbi_impl_id;
+static u_long sbi_impl_version;
 
 static bool has_time_extension = false;
 static bool has_ipi_extension = false;
@@ -316,10 +324,53 @@ sbi_init(void)
 }
 
 static void
-sbi_late_init(void *dummy __unused)
+sbi_identify(driver_t *driver, device_t parent)
+{
+	device_t dev;
+
+	if (device_find_child(parent, "sbi", -1) != NULL)
+		return;
+
+	dev = BUS_ADD_CHILD(parent, 0, "sbi", -1);
+	if (dev == NULL)
+		device_printf(parent, "Can't add sbi child\n");
+}
+
+static int
+sbi_probe(device_t dev)
 {
+	device_set_desc(dev, "RISC-V Supervisor Binary Interface");
+
+	return (BUS_PROBE_NOWILDCARD);
+}
+
+static int
+sbi_attach(device_t dev)
+{
+	struct sbi_softc *sc;
+
+	if (sbi_softc != NULL)
+		return (ENXIO);
+
+	sc = device_get_softc(dev);
+	sc->dev = dev;
+	sbi_softc = sc;
+
 	EVENTHANDLER_REGISTER(shutdown_final, sbi_shutdown_final, NULL,
 	    SHUTDOWN_PRI_LAST);
+
+	return (0);
 }
 
-SYSINIT(sbi, SI_SUB_KLD, SI_ORDER_ANY, sbi_late_init, NULL);
+static device_method_t sbi_methods[] = {
+	/* Device interface */
+	DEVMETHOD(device_identify,	sbi_identify),
+	DEVMETHOD(device_probe,		sbi_probe),
+	DEVMETHOD(device_attach,	sbi_attach),
+
+	DEVMETHOD_END
+};
+
+DEFINE_CLASS_0(sbi, sbi_driver, sbi_methods, sizeof(struct sbi_softc));
+EARLY_DRIVER_MODULE(sbi, nexus, sbi_driver, 0, 0,
+    BUS_PASS_CPU + BUS_PASS_ORDER_FIRST);