1 files changed, 522 insertions, 0 deletions
diff --git a/drivers/sfi/sfi_core.c b/drivers/sfi/sfi_core.c
new file mode 100644
index 000000000..a5136901d
--- /dev/null
+++ b/drivers/sfi/sfi_core.c
@@ -0,0 +1,522 @@
+/* sfi_core.c Simple Firmware Interface - core internals */
+
+/*
+
+  This file is provided under a dual BSD/GPLv2 license.  When using or
+  redistributing this file, you may do so under either license.
+
+  GPL LICENSE SUMMARY
+
+  Copyright(c) 2009 Intel Corporation. All rights reserved.
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of version 2 of the GNU General Public License as
+  published by the Free Software Foundation.
+
+  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 St - Fifth Floor, Boston, MA 02110-1301 USA.
+  The full GNU General Public License is included in this distribution
+  in the file called LICENSE.GPL.
+
+  BSD LICENSE
+
+  Copyright(c) 2009 Intel Corporation. All rights reserved.
+
+  Redistribution and use in source and binary forms, with or without
+  modification, are permitted provided that the following conditions
+  are met:
+
+    * Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above copyright
+      notice, this list of conditions and the following disclaimer in
+      the documentation and/or other materials provided with the
+      distribution.
+    * Neither the name of Intel Corporation nor the names of its
+      contributors may be used to endorse or promote products derived
+      from this software without specific prior written permission.
+
+  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+  A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+  OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+  LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+  DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+  THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+*/
+
+#define KMSG_COMPONENT "SFI"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
+
+#include <linux/memblock.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/acpi.h>
+#include <linux/init.h>
+#include <linux/sfi.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+
+#include "sfi_core.h"
+
+#define ON_SAME_PAGE(addr1, addr2) \
+	(((unsigned long)(addr1) & PAGE_MASK) == \
+	((unsigned long)(addr2) & PAGE_MASK))
+#define TABLE_ON_PAGE(page, table, size) (ON_SAME_PAGE(page, table) && \
+				ON_SAME_PAGE(page, table + size))
+
+int sfi_disabled __read_mostly;
+EXPORT_SYMBOL(sfi_disabled);
+
+static u64 syst_pa __read_mostly;
+static struct sfi_table_simple *syst_va __read_mostly;
+
+/*
+ * FW creates and saves the SFI tables in memory. When these tables get
+ * used, they may need to be mapped to virtual address space, and the mapping
+ * can happen before or after the memremap() is ready, so a flag is needed
+ * to indicating this
+ */
+static u32 sfi_use_memremap __read_mostly;
+
+/*
+ * sfi_un/map_memory calls early_memremap/memunmap which is a __init function
+ * and introduces section mismatch. So use __ref to make it calm.
+ */
+static void __iomem * __ref sfi_map_memory(u64 phys, u32 size)
+{
+	if (!phys || !size)
+		return NULL;
+
+	if (sfi_use_memremap)
+		return memremap(phys, size, MEMREMAP_WB);
+	else
+		return early_memremap(phys, size);
+}
+
+static void __ref sfi_unmap_memory(void __iomem *virt, u32 size)
+{
+	if (!virt || !size)
+		return;
+
+	if (sfi_use_memremap)
+		memunmap(virt);
+	else
+		early_memunmap(virt, size);
+}
+
+static void sfi_print_table_header(unsigned long long pa,
+				struct sfi_table_header *header)
+{
+	pr_info("%4.4s %llX, %04X (v%d %6.6s %8.8s)\n",
+		header->sig, pa,
+		header->len, header->rev, header->oem_id,
+		header->oem_table_id);
+}
+
+/*
+ * sfi_verify_table()
+ * Sanity check table lengh, calculate checksum
+ */
+static int sfi_verify_table(struct sfi_table_header *table)
+{
+
+	u8 checksum = 0;
+	u8 *puchar = (u8 *)table;
+	u32 length = table->len;
+
+	/* Sanity check table length against arbitrary 1MB limit */
+	if (length > 0x100000) {
+		pr_err("Invalid table length 0x%x\n", length);
+		return -1;
+	}
+
+	while (length--)
+		checksum += *puchar++;
+
+	if (checksum) {
+		pr_err("Checksum %2.2X should be %2.2X\n",
+			table->csum, table->csum - checksum);
+		return -1;
+	}
+	return 0;
+}
+
+/*
+ * sfi_map_table()
+ *
+ * Return address of mapped table
+ * Check for common case that we can re-use mapping to SYST,
+ * which requires syst_pa, syst_va to be initialized.
+ */
+static struct sfi_table_header *sfi_map_table(u64 pa)
+{
+	struct sfi_table_header *th;
+	u32 length;
+
+	if (!TABLE_ON_PAGE(syst_pa, pa, sizeof(struct sfi_table_header)))
+		th = sfi_map_memory(pa, sizeof(struct sfi_table_header));
+	else
+		th = (void *)syst_va + (pa - syst_pa);
+
+	 /* If table fits on same page as its header, we are done */
+	if (TABLE_ON_PAGE(th, th, th->len))
+		return th;
+
+	/* Entire table does not fit on same page as SYST */
+	length = th->len;
+	if (!TABLE_ON_PAGE(syst_pa, pa, sizeof(struct sfi_table_header)))
+		sfi_unmap_memory(th, sizeof(struct sfi_table_header));
+
+	return sfi_map_memory(pa, length);
+}
+
+/*
+ * sfi_unmap_table()
+ *
+ * Undoes effect of sfi_map_table() by unmapping table
+ * if it did not completely fit on same page as SYST.
+ */
+static void sfi_unmap_table(struct sfi_table_header *th)
+{
+	if (!TABLE_ON_PAGE(syst_va, th, th->len))
+		sfi_unmap_memory(th, TABLE_ON_PAGE(th, th, th->len) ?
+					sizeof(*th) : th->len);
+}
+
+static int sfi_table_check_key(struct sfi_table_header *th,
+				struct sfi_table_key *key)
+{
+
+	if (strncmp(th->sig, key->sig, SFI_SIGNATURE_SIZE)
+		|| (key->oem_id && strncmp(th->oem_id,
+				key->oem_id, SFI_OEM_ID_SIZE))
+		|| (key->oem_table_id && strncmp(th->oem_table_id,
+				key->oem_table_id, SFI_OEM_TABLE_ID_SIZE)))
+		return -1;
+
+	return 0;
+}
+
+/*
+ * This function will be used in 2 cases:
+ * 1. used to enumerate and verify the tables addressed by SYST/XSDT,
+ *    thus no signature will be given (in kernel boot phase)
+ * 2. used to parse one specific table, signature must exist, and
+ *    the mapped virt address will be returned, and the virt space
+ *    will be released by call sfi_put_table() later
+ *
+ * This two cases are from two different functions with two different
+ * sections and causes section mismatch warning. So use __ref to tell
+ * modpost not to make any noise.
+ *
+ * Return value:
+ *	NULL:			when can't find a table matching the key
+ *	ERR_PTR(error):		error value
+ *	virt table address:	when a matched table is found
+ */
+struct sfi_table_header *
+ __ref sfi_check_table(u64 pa, struct sfi_table_key *key)
+{
+	struct sfi_table_header *th;
+	void *ret = NULL;
+
+	th = sfi_map_table(pa);
+	if (!th)
+		return ERR_PTR(-ENOMEM);
+
+	if (!key->sig) {
+		sfi_print_table_header(pa, th);
+		if (sfi_verify_table(th))
+			ret = ERR_PTR(-EINVAL);
+	} else {
+		if (!sfi_table_check_key(th, key))
+			return th;	/* Success */
+	}
+
+	sfi_unmap_table(th);
+	return ret;
+}
+
+/*
+ * sfi_get_table()
+ *
+ * Search SYST for the specified table with the signature in
+ * the key, and return the mapped table
+ */
+struct sfi_table_header *sfi_get_table(struct sfi_table_key *key)
+{
+	struct sfi_table_header *th;
+	u32 tbl_cnt, i;
+
+	tbl_cnt = SFI_GET_NUM_ENTRIES(syst_va, u64);
+	for (i = 0; i < tbl_cnt; i++) {
+		th = sfi_check_table(syst_va->pentry[i], key);
+		if (!IS_ERR(th) && th)
+			return th;
+	}
+
+	return NULL;
+}
+
+void sfi_put_table(struct sfi_table_header *th)
+{
+	sfi_unmap_table(th);
+}
+
+/* Find table with signature, run handler on it */
+int sfi_table_parse(char *signature, char *oem_id, char *oem_table_id,
+			sfi_table_handler handler)
+{
+	struct sfi_table_header *table = NULL;
+	struct sfi_table_key key;
+	int ret = -EINVAL;
+
+	if (sfi_disabled || !handler || !signature)
+		goto exit;
+
+	key.sig = signature;
+	key.oem_id = oem_id;
+	key.oem_table_id = oem_table_id;
+
+	table = sfi_get_table(&key);
+	if (!table)
+		goto exit;
+
+	ret = handler(table);
+	sfi_put_table(table);
+exit:
+	return ret;
+}
+EXPORT_SYMBOL_GPL(sfi_table_parse);
+
+/*
+ * sfi_parse_syst()
+ * Checksum all the tables in SYST and print their headers
+ *
+ * success: set syst_va, return 0
+ */
+static int __init sfi_parse_syst(void)
+{
+	struct sfi_table_key key = SFI_ANY_KEY;
+	int tbl_cnt, i;
+	void *ret;
+
+	syst_va = sfi_map_memory(syst_pa, sizeof(struct sfi_table_simple));
+	if (!syst_va)
+		return -ENOMEM;
+
+	tbl_cnt = SFI_GET_NUM_ENTRIES(syst_va, u64);
+	for (i = 0; i < tbl_cnt; i++) {
+		ret = sfi_check_table(syst_va->pentry[i], &key);
+		if (IS_ERR(ret))
+			return PTR_ERR(ret);
+	}
+
+	return 0;
+}
+
+/*
+ * The OS finds the System Table by searching 16-byte boundaries between
+ * physical address 0x000E0000 and 0x000FFFFF. The OS shall search this region
+ * starting at the low address and shall stop searching when the 1st valid SFI
+ * System Table is found.
+ *
+ * success: set syst_pa, return 0
+ * fail: return -1
+ */
+static __init int sfi_find_syst(void)
+{
+	unsigned long offset, len;
+	void *start;
+
+	len = SFI_SYST_SEARCH_END - SFI_SYST_SEARCH_BEGIN;
+	start = sfi_map_memory(SFI_SYST_SEARCH_BEGIN, len);
+	if (!start)
+		return -1;
+
+	for (offset = 0; offset < len; offset += 16) {
+		struct sfi_table_header *syst_hdr;
+
+		syst_hdr = start + offset;
+		if (strncmp(syst_hdr->sig, SFI_SIG_SYST,
+				SFI_SIGNATURE_SIZE))
+			continue;
+
+		if (syst_hdr->len > PAGE_SIZE)
+			continue;
+
+		sfi_print_table_header(SFI_SYST_SEARCH_BEGIN + offset,
+					syst_hdr);
+
+		if (sfi_verify_table(syst_hdr))
+			continue;
+
+		/*
+		 * Enforce SFI spec mandate that SYST reside within a page.
+		 */
+		if (!ON_SAME_PAGE(syst_pa, syst_pa + syst_hdr->len)) {
+			pr_info("SYST 0x%llx + 0x%x crosses page\n",
+					syst_pa, syst_hdr->len);
+			continue;
+		}
+
+		/* Success */
+		syst_pa = SFI_SYST_SEARCH_BEGIN + offset;
+		sfi_unmap_memory(start, len);
+		return 0;
+	}
+
+	sfi_unmap_memory(start, len);
+	return -1;
+}
+
+static struct kobject *sfi_kobj;
+static struct kobject *tables_kobj;
+
+static ssize_t sfi_table_show(struct file *filp, struct kobject *kobj,
+			       struct bin_attribute *bin_attr, char *buf,
+			       loff_t offset, size_t count)
+{
+	struct sfi_table_attr *tbl_attr =
+	    container_of(bin_attr, struct sfi_table_attr, attr);
+	struct sfi_table_header *th = NULL;
+	struct sfi_table_key key;
+	ssize_t cnt;
+
+	key.sig = tbl_attr->name;
+	key.oem_id = NULL;
+	key.oem_table_id = NULL;
+
+	if (strncmp(SFI_SIG_SYST, tbl_attr->name, SFI_SIGNATURE_SIZE)) {
+		th = sfi_get_table(&key);
+		if (!th)
+			return 0;
+
+		cnt =  memory_read_from_buffer(buf, count, &offset,
+						th, th->len);
+		sfi_put_table(th);
+	} else
+		cnt =  memory_read_from_buffer(buf, count, &offset,
+					syst_va, syst_va->header.len);
+
+	return cnt;
+}
+
+struct sfi_table_attr __init *sfi_sysfs_install_table(u64 pa)
+{
+	struct sfi_table_attr *tbl_attr;
+	struct sfi_table_header *th;
+	int ret;
+
+	tbl_attr = kzalloc(sizeof(struct sfi_table_attr), GFP_KERNEL);
+	if (!tbl_attr)
+		return NULL;
+
+	th = sfi_map_table(pa);
+	if (!th || !th->sig[0]) {
+		kfree(tbl_attr);
+		return NULL;
+	}
+
+	sysfs_attr_init(&tbl_attr->attr.attr);
+	memcpy(tbl_attr->name, th->sig, SFI_SIGNATURE_SIZE);
+
+	tbl_attr->attr.size = 0;
+	tbl_attr->attr.read = sfi_table_show;
+	tbl_attr->attr.attr.name = tbl_attr->name;
+	tbl_attr->attr.attr.mode = 0400;
+
+	ret = sysfs_create_bin_file(tables_kobj,
+				  &tbl_attr->attr);
+	if (ret) {
+		kfree(tbl_attr);
+		tbl_attr = NULL;
+	}
+
+	sfi_unmap_table(th);
+	return tbl_attr;
+}
+
+static int __init sfi_sysfs_init(void)
+{
+	int tbl_cnt, i;
+
+	if (sfi_disabled)
+		return 0;
+
+	sfi_kobj = kobject_create_and_add("sfi", firmware_kobj);
+	if (!sfi_kobj)
+		return 0;
+
+	tables_kobj = kobject_create_and_add("tables", sfi_kobj);
+	if (!tables_kobj) {
+		kobject_put(sfi_kobj);
+		return 0;
+	}
+
+	sfi_sysfs_install_table(syst_pa);
+
+	tbl_cnt = SFI_GET_NUM_ENTRIES(syst_va, u64);
+
+	for (i = 0; i < tbl_cnt; i++)
+		sfi_sysfs_install_table(syst_va->pentry[i]);
+
+	sfi_acpi_sysfs_init();
+	kobject_uevent(sfi_kobj, KOBJ_ADD);
+	kobject_uevent(tables_kobj, KOBJ_ADD);
+	pr_info("SFI sysfs interfaces init success\n");
+	return 0;
+}
+
+void __init sfi_init(void)
+{
+	if (!acpi_disabled)
+		disable_sfi();
+
+	if (sfi_disabled)
+		return;
+
+	pr_info("Simple Firmware Interface v0.81 http://simplefirmware.org\n");
+
+	if (sfi_find_syst() || sfi_parse_syst() || sfi_platform_init())
+		disable_sfi();
+
+	return;
+}
+
+void __init sfi_init_late(void)
+{
+	int length;
+
+	if (sfi_disabled)
+		return;
+
+	length = syst_va->header.len;
+	sfi_unmap_memory(syst_va, sizeof(struct sfi_table_simple));
+
+	/* Use memremap now after it is ready */
+	sfi_use_memremap = 1;
+	syst_va = sfi_map_memory(syst_pa, length);
+
+	sfi_acpi_init();
+}
+
+/*
+ * The reason we put it here because we need wait till the /sys/firmware
+ * is setup, then our interface can be registered in /sys/firmware/sfi
+ */
+core_initcall(sfi_sysfs_init);