acpi: move generic aml building helpers into dedictated file

the will be later used for composing AML primitives
and all that could be reused later for ARM machines
as well.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Acked-by: Marcel Apfelbaum <marcel@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

1 files changed, 187 insertions, 0 deletions

diff --git a/hw/acpi/aml-build.c b/hw/acpi/aml-build.c
new file mode 100644
index 0000000000..b28c1f41a5
--- /dev/null
+++ b/hw/acpi/aml-build.c
@@ -0,0 +1,187 @@
+/* Support for generating ACPI tables and passing them to Guests
+ *
+ * Copyright (C) 2015 Red Hat Inc
+ *
+ * Author: Michael S. Tsirkin <mst@redhat.com>
+ * Author: Igor Mammedov <imammedo@redhat.com>
+ *
+ * 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
+ * (at your option) 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <stdio.h>
+#include <stdarg.h>
+#include <assert.h>
+#include <stdbool.h>
+#include "hw/acpi/aml-build.h"
+
+GArray *build_alloc_array(void)
+{
+    return g_array_new(false, true /* clear */, 1);
+}
+
+void build_free_array(GArray *array)
+{
+    g_array_free(array, true);
+}
+
+void build_prepend_byte(GArray *array, uint8_t val)
+{
+    g_array_prepend_val(array, val);
+}
+
+void build_append_byte(GArray *array, uint8_t val)
+{
+    g_array_append_val(array, val);
+}
+
+void build_append_array(GArray *array, GArray *val)
+{
+    g_array_append_vals(array, val->data, val->len);
+}
+
+#define ACPI_NAMESEG_LEN 4
+
+void GCC_FMT_ATTR(2, 3)
+build_append_nameseg(GArray *array, const char *format, ...)
+{
+    /* It would be nicer to use g_string_vprintf but it's only there in 2.22 */
+    char s[] = "XXXX";
+    int len;
+    va_list args;
+
+    va_start(args, format);
+    len = vsnprintf(s, sizeof s, format, args);
+    va_end(args);
+
+    assert(len <= ACPI_NAMESEG_LEN);
+
+    g_array_append_vals(array, s, len);
+    /* Pad up to ACPI_NAMESEG_LEN characters if necessary. */
+    g_array_append_vals(array, "____", ACPI_NAMESEG_LEN - len);
+}
+
+/* 5.4 Definition Block Encoding */
+enum {
+    PACKAGE_LENGTH_1BYTE_SHIFT = 6, /* Up to 63 - use extra 2 bits. */
+    PACKAGE_LENGTH_2BYTE_SHIFT = 4,
+    PACKAGE_LENGTH_3BYTE_SHIFT = 12,
+    PACKAGE_LENGTH_4BYTE_SHIFT = 20,
+};
+
+void build_prepend_package_length(GArray *package, unsigned min_bytes)
+{
+    uint8_t byte;
+    unsigned length = package->len;
+    unsigned length_bytes;
+
+    if (length + 1 < (1 << PACKAGE_LENGTH_1BYTE_SHIFT)) {
+        length_bytes = 1;
+    } else if (length + 2 < (1 << PACKAGE_LENGTH_3BYTE_SHIFT)) {
+        length_bytes = 2;
+    } else if (length + 3 < (1 << PACKAGE_LENGTH_4BYTE_SHIFT)) {
+        length_bytes = 3;
+    } else {
+        length_bytes = 4;
+    }
+
+    /* Force length to at least min_bytes.
+     * This wastes memory but that's how bios did it.
+     */
+    length_bytes = MAX(length_bytes, min_bytes);
+
+    /* PkgLength is the length of the inclusive length of the data. */
+    length += length_bytes;
+
+    switch (length_bytes) {
+    case 1:
+        byte = length;
+        build_prepend_byte(package, byte);
+        return;
+    case 4:
+        byte = length >> PACKAGE_LENGTH_4BYTE_SHIFT;
+        build_prepend_byte(package, byte);
+        length &= (1 << PACKAGE_LENGTH_4BYTE_SHIFT) - 1;
+        /* fall through */
+    case 3:
+        byte = length >> PACKAGE_LENGTH_3BYTE_SHIFT;
+        build_prepend_byte(package, byte);
+        length &= (1 << PACKAGE_LENGTH_3BYTE_SHIFT) - 1;
+        /* fall through */
+    case 2:
+        byte = length >> PACKAGE_LENGTH_2BYTE_SHIFT;
+        build_prepend_byte(package, byte);
+        length &= (1 << PACKAGE_LENGTH_2BYTE_SHIFT) - 1;
+        /* fall through */
+    }
+    /*
+     * Most significant two bits of byte zero indicate how many following bytes
+     * are in PkgLength encoding.
+     */
+    byte = ((length_bytes - 1) << PACKAGE_LENGTH_1BYTE_SHIFT) | length;
+    build_prepend_byte(package, byte);
+}
+
+void build_package(GArray *package, uint8_t op, unsigned min_bytes)
+{
+    build_prepend_package_length(package, min_bytes);
+    build_prepend_byte(package, op);
+}
+
+void build_extop_package(GArray *package, uint8_t op)
+{
+    build_package(package, op, 1);
+    build_prepend_byte(package, 0x5B); /* ExtOpPrefix */
+}
+
+void build_append_value(GArray *table, uint32_t value, int size)
+{
+    uint8_t prefix;
+    int i;
+
+    switch (size) {
+    case 1:
+        prefix = 0x0A; /* BytePrefix */
+        break;
+    case 2:
+        prefix = 0x0B; /* WordPrefix */
+        break;
+    case 4:
+        prefix = 0x0C; /* DWordPrefix */
+        break;
+    default:
+        assert(0);
+        return;
+    }
+    build_append_byte(table, prefix);
+    for (i = 0; i < size; ++i) {
+        build_append_byte(table, value & 0xFF);
+        value = value >> 8;
+    }
+}
+
+void build_append_int(GArray *table, uint32_t value)
+{
+    if (value == 0x00) {
+        build_append_byte(table, 0x00); /* ZeroOp */
+    } else if (value == 0x01) {
+        build_append_byte(table, 0x01); /* OneOp */
+    } else if (value <= 0xFF) {
+        build_append_value(table, value, 1);
+    } else if (value <= 0xFFFF) {
+        build_append_value(table, value, 2);
+    } else {
+        build_append_value(table, value, 4);
+    }
+}
+