Merge branch 'master' into openslxopenslx

1 files changed, 100 insertions, 0 deletions

diff --git a/src/arch/riscv/core/hart.c b/src/arch/riscv/core/hart.c
new file mode 100644
index 000000000..d9cfb4e5d
--- /dev/null
+++ b/src/arch/riscv/core/hart.c
@@ -0,0 +1,100 @@
+/*
+ * Copyright (C) 2024 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ *
+ * You can also choose to distribute this program under the terms of
+ * the Unmodified Binary Distribution Licence (as given in the file
+ * COPYING.UBDL), provided that you have satisfied its requirements.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
+
+/** @file
+ *
+ * Hardware threads (harts)
+ *
+ */
+
+#include <string.h>
+#include <stdio.h>
+#include <errno.h>
+#include <ipxe/fdt.h>
+#include <ipxe/hart.h>
+
+/** Boot hart ID */
+unsigned long boot_hart;
+
+/** Colour for debug messages */
+#define colour &boot_hart
+
+/**
+ * Find boot hart node
+ *
+ * @v offset		Boot hart node offset
+ * @ret rc		Return status code
+ */
+static int hart_node ( unsigned int *offset ) {
+	char path[27 /* "/cpus/cpu@XXXXXXXXXXXXXXXX" + NUL */ ];
+	int rc;
+
+	/* Construct node path */
+	snprintf ( path, sizeof ( path ), "/cpus/cpu@%lx", boot_hart );
+
+	/* Find node */
+	if ( ( rc = fdt_path ( &sysfdt, path, offset ) ) != 0 ) {
+		DBGC ( colour, "HART could not find %s: %s\n",
+		       path, strerror ( rc ) );
+		return rc;
+	}
+
+	return 0;
+}
+
+/**
+ * Check for supported extension
+ *
+ * @v ext		Extension name (including leading underscore)
+ * @ret rc		Return status code
+ */
+int hart_supported ( const char *ext ) {
+	unsigned int offset;
+	const char *isa;
+	const char *tmp;
+	int rc;
+
+	/* Find boot hart node */
+	if ( ( rc = hart_node ( &offset ) ) != 0 )
+		return rc;
+
+	/* Get ISA description */
+	isa = fdt_string ( &sysfdt, offset, "riscv,isa" );
+	if ( ! isa ) {
+		DBGC ( colour, "HART could not identify ISA\n" );
+		return -ENOENT;
+	}
+	DBGC ( colour, "HART supports %s\n", isa );
+
+	/* Check for presence of extension */
+	tmp = isa;
+	while ( ( tmp = strstr ( tmp, ext ) ) != NULL ) {
+		tmp += strlen ( ext );
+		if ( ( *tmp == '\0' ) || ( *tmp == '_' ) )
+			return 0;
+	}
+
+	return -ENOTSUP;
+}