--- /dev/null
+/* 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/bootmem.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 "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 ioremap() is ready, so a flag is needed
+ * to indicating this
+ */
+static u32 sfi_use_ioremap __read_mostly;
+
+/*
+ * sfi_un/map_memory calls early_ioremap/iounmap 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_ioremap)
+ return ioremap_cache(phys, size);
+ else
+ return early_ioremap(phys, size);
+}
+
+static void __ref sfi_unmap_memory(void __iomem *virt, u32 size)
+{
+ if (!virt || !size)
+ return;
+
+ if (sfi_use_ioremap)
+ iounmap(virt);
+ else
+ early_iounmap(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 ioremap now after it is ready */
+ sfi_use_ioremap = 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);
Code Review / kvmfornfv.git / blobdiff