SFI: add platform-independent core support

drivers/sfi/sfi_core.c contains the generic SFI implementation.
It has a private header, sfi_core.h, for its own use and the
private use of future files in drivers/sfi/

Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

3 files changed, 485 insertions, 0 deletions

diff --git a/drivers/sfi/Makefile b/drivers/sfi/Makefile
new file mode 100644
index 000000000000..2343732aefeb
--- /dev/null
+++ b/drivers/sfi/Makefile
@@ -0,0 +1,3 @@
+obj-y   += sfi_acpi.o
+obj-y   += sfi_core.o
+
diff --git a/drivers/sfi/sfi_core.c b/drivers/sfi/sfi_core.c
new file mode 100644
index 000000000000..7bd6b18fdd27
--- /dev/null
+++ b/drivers/sfi/sfi_core.c
@@ -0,0 +1,412 @@
+/* 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/string.h>
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/acpi.h>
+#include <linux/init.h>
+#include <linux/irq.h>
+#include <linux/sfi.h>
+#include <linux/smp.h>
+
+#include <asm/pgtable.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;
+
+static void __iomem *sfi_map_memory(u64 phys, u32 size)
+{
+        if (!phys || !size)
+                return NULL;
+
+        if (sfi_use_ioremap)
+                return ioremap(phys, size);
+        else
+                return early_ioremap(phys, size);
+}
+
+static void 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 __init 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.
+ */
+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.
+ */
+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
+ *
+ * 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 *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;
+}
+
+void __init sfi_init(void)
+{
+        if (!acpi_disabled)
+                disable_sfi();
+
+        if (sfi_disabled)
+                return;
+
+        pr_info("Simple Firmware Interface v0.7 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();
+}
diff --git a/drivers/sfi/sfi_core.h b/drivers/sfi/sfi_core.h
new file mode 100644
index 000000000000..da82d39e104d
--- /dev/null
+++ b/drivers/sfi/sfi_core.h
@@ -0,0 +1,70 @@
+/* sfi_core.h Simple Firmware Interface, internal header */
+
+/*
+
+  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.
+
+*/
+struct sfi_table_key{
+        char    *sig;
+        char    *oem_id;
+        char    *oem_table_id;
+};
+
+#define SFI_ANY_KEY { .sig = NULL, .oem_id = NULL, .oem_table_id = NULL }
+
+extern int __init sfi_acpi_init(void);
+extern  struct sfi_table_header *sfi_check_table(u64 paddr,
+                                        struct sfi_table_key *key);
+struct sfi_table_header *sfi_get_table(struct sfi_table_key *key);
+extern void sfi_put_table(struct sfi_table_header *table);