Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932146AbbGUNbX (ORCPT ); Tue, 21 Jul 2015 09:31:23 -0400 Received: from mail-wi0-f180.google.com ([209.85.212.180]:34795 "EHLO mail-wi0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754858AbbGUNbU (ORCPT ); Tue, 21 Jul 2015 09:31:20 -0400 From: Graeme Gregory To: rjw@rjwysocki.net, lenb@kernel.org, linux-acpi@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Graeme Gregory Subject: [RFC PATCH] ACPI: sysfs expose root tables RSDP/RSDT/XSDT Date: Tue, 21 Jul 2015 14:31:08 +0100 Message-Id: <1437485468-17107-2-git-send-email-graeme.gregory@linaro.org> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1437485468-17107-1-git-send-email-graeme.gregory@linaro.org> References: <1437485468-17107-1-git-send-email-graeme.gregory@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4535 Lines: 158 On some architectures /dev/mem is being removed. For debug/analysis tools like FWTS/acpidump we therefore need to expose the ACPI root tables in sysfs like the other tables. Signed-off-by: Graeme Gregory --- drivers/acpi/sysfs.c | 123 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 123 insertions(+) diff --git a/drivers/acpi/sysfs.c b/drivers/acpi/sysfs.c index 0876d77b..c998ea1 100644 --- a/drivers/acpi/sysfs.c +++ b/drivers/acpi/sysfs.c @@ -348,6 +348,127 @@ acpi_sysfs_table_handler(u32 event, void *table, void *context) return AE_OK; } +/* + * On some architectures /dev/mem interface is not available so for debug + * tools like FWTS, acpidump etc we will also need to export the three + * root tables RSDP, RSDT, XSDT where they exist. + */ + +struct acpi_root_table_attr { + struct bin_attribute attr; + acpi_physical_address table_addr; +}; + +static ssize_t acpi_table_show_root(struct file *filp, struct kobject *kobj, + struct bin_attribute *bin_attr, char *buf, + loff_t offset, size_t count) +{ + struct acpi_root_table_attr *table_attr = + container_of(bin_attr, + struct acpi_root_table_attr, attr); + void *table; + int ret; + + table = acpi_os_map_memory(table_attr->table_addr, bin_attr->size); + + if (!table) + return -EIO; + + ret = memory_read_from_buffer(buf, count, &offset, table, + bin_attr->size); + acpi_os_unmap_memory(table, bin_attr->size); + + return ret; +} + +static int acpi_root_tables_sysfs_init(struct kobject *tables_kobj) +{ + struct acpi_root_table_attr *root_tables_attr; + struct acpi_table_rsdp *rsdp; + struct acpi_table_header *table_header = NULL; + acpi_physical_address rsdp_ptr, rsdt_ptr, xsdt_ptr; + int ret; + + rsdp_ptr = acpi_os_get_root_pointer(); + + if (!rsdp_ptr) + return -EIO; + + rsdp = acpi_os_map_memory(rsdp_ptr, sizeof(*rsdp)); + if (!rsdp) { + ret = -EIO; + goto err; + } + + root_tables_attr = kzalloc(sizeof(*root_tables_attr) * 3, GFP_KERNEL); + if (!root_tables_attr) { + ret = -ENOMEM; + goto err; + } + + root_tables_attr[0].table_addr = rsdp_ptr; + root_tables_attr[0].attr.size = sizeof(*rsdp); + root_tables_attr[0].attr.read = acpi_table_show_root; + root_tables_attr[0].attr.attr.name = "RSDP"; + root_tables_attr[0].attr.attr.mode = 0400; + + ret = sysfs_create_bin_file(tables_kobj, &root_tables_attr[0].attr); + if (ret) + goto err; + + rsdt_ptr = rsdp->rsdt_physical_address; + if (rsdt_ptr) { + table_header = acpi_os_map_memory(rsdt_ptr, + sizeof(*table_header)); + if (!table_header) { + ret = -EIO; + goto err; + } + + root_tables_attr[1].table_addr = rsdt_ptr; + root_tables_attr[1].attr.size = table_header->length; + root_tables_attr[1].attr.read = acpi_table_show_root; + root_tables_attr[1].attr.attr.name = "RSDT"; + root_tables_attr[1].attr.attr.mode = 0400; + + ret = sysfs_create_bin_file(tables_kobj, + &root_tables_attr[1].attr); + if (ret) + goto err; + acpi_os_unmap_memory(table_header, sizeof(*table_header)); + } + + xsdt_ptr = rsdp->xsdt_physical_address; + if (xsdt_ptr) { + table_header = acpi_os_map_memory(xsdt_ptr, + sizeof(*table_header)); + if (!table_header) { + ret = -EIO; + goto err; + } + + root_tables_attr[2].table_addr = xsdt_ptr; + root_tables_attr[2].attr.size = table_header->length; + root_tables_attr[2].attr.read = acpi_table_show_root; + root_tables_attr[2].attr.attr.name = "XSDT"; + root_tables_attr[2].attr.attr.mode = 0400; + + ret = sysfs_create_bin_file(tables_kobj, + &root_tables_attr[2].attr); + if (ret) + goto err; + acpi_os_unmap_memory(table_header, sizeof(*table_header)); + } + return ret; + +err: + if (rsdp) + acpi_os_map_memory(rsdp_ptr, sizeof(*rsdp)); + if (table_header) + acpi_os_unmap_memory(table_header, sizeof(*table_header)); + return ret; +} + static int acpi_tables_sysfs_init(void) { struct acpi_table_attr *table_attr; @@ -387,6 +508,8 @@ static int acpi_tables_sysfs_init(void) list_add_tail(&table_attr->node, &acpi_table_attr_list); } + acpi_root_tables_sysfs_init(tables_kobj); + kobject_uevent(tables_kobj, KOBJ_ADD); kobject_uevent(dynamic_tables_kobj, KOBJ_ADD); status = acpi_install_table_handler(acpi_sysfs_table_handler, NULL); -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/