From mboxrd@z Thu Jan 1 00:00:00 1970 From: Shannon Zhao Subject: [PATCH v4 10/21] acpi/table: Introduce acpi_table_get_entry_madt to get specified entry Date: Sat, 23 Jan 2016 17:20:02 +0800 Message-ID: <1453540813-15764-11-git-send-email-zhaoshenglong@huawei.com> References: <1453540813-15764-1-git-send-email-zhaoshenglong@huawei.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1453540813-15764-1-git-send-email-zhaoshenglong@huawei.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: xen-devel@lists.xen.org Cc: ian.campbell@citrix.com, stefano.stabellini@eu.citrix.com, peter.huangpeng@huawei.com, julien.grall@citrix.com, stefano.stabellini@citrix.com, shannon.zhao@linaro.org, Jan Beulich List-Id: xen-devel@lists.xenproject.org From: Shannon Zhao This function could get the specified index entry of MADT table. This would be useful when it needs to get the contens of the entry. Cc: Jan Beulich Signed-off-by: Shannon Zhao --- V4: Fix coding style and make the function only for MADT table --- xen/drivers/acpi/tables.c | 59 +++++++++++++++++++++++++++++++++++++++++++++++ xen/include/xen/acpi.h | 2 ++ 2 files changed, 61 insertions(+) diff --git a/xen/drivers/acpi/tables.c b/xen/drivers/acpi/tables.c index 84a290f..c50bae4 100644 --- a/xen/drivers/acpi/tables.c +++ b/xen/drivers/acpi/tables.c @@ -219,6 +219,65 @@ void __init acpi_table_print_madt_entry(struct acpi_subtable_header *header) } } +static struct acpi_subtable_header * __init +acpi_get_entry(char *id, unsigned long table_size, + struct acpi_table_header *table_header, int entry_id, + unsigned int entry_index) +{ + struct acpi_subtable_header *entry; + int count = 0; + unsigned long table_end; + + if (!table_size) + return NULL; + + if (!table_header) { + printk(KERN_WARNING PREFIX "%4.4s not present\n", id); + return NULL; + } + + table_end = (unsigned long)table_header + table_header->length; + + /* Parse all entries looking for a match. */ + entry = (struct acpi_subtable_header *) + ((unsigned long)table_header + table_size); + + while (((unsigned long)entry) + sizeof(struct acpi_subtable_header) < + table_end) { + if (entry->length < sizeof(*entry)) { + printk(KERN_ERR PREFIX "[%4.4s:%#x] Invalid length\n", + id, entry_id); + return NULL; + } + + if (entry->type == entry_id) { + if (count == entry_index) + return entry; + count++; + } + + entry = (struct acpi_subtable_header *) + ((unsigned long)entry + entry->length); + } + + return NULL; +} + +struct acpi_subtable_header * __init +acpi_table_get_entry_madt(enum acpi_madt_type id, unsigned int entry_index) +{ + struct acpi_table_header *table_header = NULL; + + acpi_get_table(ACPI_SIG_MADT, acpi_apic_instance, &table_header); + if (!table_header) { + printk(KERN_WARNING PREFIX "%4.4s not present\n", + ACPI_SIG_MADT); + return NULL; + } + + return acpi_get_entry(ACPI_SIG_MADT, sizeof(struct acpi_table_madt), + table_header, id, entry_index); +} int __init acpi_parse_entries(char *id, unsigned long table_size, diff --git a/xen/include/xen/acpi.h b/xen/include/xen/acpi.h index bc73310..32d7a4f 100644 --- a/xen/include/xen/acpi.h +++ b/xen/include/xen/acpi.h @@ -74,6 +74,8 @@ int acpi_parse_entries(char *id, unsigned long table_size, int entry_id, unsigned int max_entries); int acpi_table_parse_entries(char *id, unsigned long table_size, int entry_id, acpi_table_entry_handler handler, unsigned int max_entries); +struct acpi_subtable_header *acpi_table_get_entry_madt(enum acpi_madt_type id, + unsigned int entry_index); int acpi_table_parse_madt(enum acpi_madt_type id, acpi_table_entry_handler handler, unsigned int max_entries); int acpi_table_parse_srat(int id, acpi_madt_entry_handler handler, unsigned int max_entries); -- 2.0.4