Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754815AbbFSIrp (ORCPT ); Fri, 19 Jun 2015 04:47:45 -0400 Received: from mail-pa0-f53.google.com ([209.85.220.53]:33978 "EHLO mail-pa0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754658AbbFSIqr (ORCPT ); Fri, 19 Jun 2015 04:46:47 -0400 From: Hanjun Guo To: Marc Zyngier , Jason Cooper , Will Deacon , Catalin Marinas , "Rafael J. Wysocki" Cc: Thomas Gleixner , Jiang Liu , Lorenzo Pieralisi , Arnd Bergmann , Tomasz Nowicki , Grant Likely , Olof Johansson , Wei Huang , linux-arm-kernel@lists.infradead.org, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, linaro-acpi@lists.linaro.org, Hanjun Guo Subject: [PATCH v2 4/9] ACPI / irqchip: Add self-probe infrastructure to initialize IRQ controller Date: Fri, 19 Jun 2015 16:46:07 +0800 Message-Id: <1434703572-26221-5-git-send-email-hanjun.guo@linaro.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1434703572-26221-1-git-send-email-hanjun.guo@linaro.org> References: <1434703572-26221-1-git-send-email-hanjun.guo@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5433 Lines: 173 This self-probe infrastructure works in the similar way as OF, but there is some different in the mechanism: For DT, the init fn will be called once it finds compatible strings in DT, but for ACPI, we init irqchips by static tables, and in static ACPI tables, there are no compatible strings to indicate irqchips, but thanks to the GIC version presented in ACPI table, we can call the corresponding GIC drivers matching the GIC version with this framework. This mechanism can also be used for clock declare and may also works on x86 for some table parsing too. Part of this patch is based on Tomasz Nowicki's work. Signed-off-by: Tomasz Nowicki Signed-off-by: Hanjun Guo --- drivers/irqchip/irq-gic-acpi.c | 29 +++++++++++++++++++++++++++++ drivers/irqchip/irqchip.h | 12 ++++++++++++ include/asm-generic/vmlinux.lds.h | 13 +++++++++++++ include/linux/acpi.h | 16 ++++++++++++++++ include/linux/mod_devicetable.h | 8 ++++++++ 5 files changed, 78 insertions(+) diff --git a/drivers/irqchip/irq-gic-acpi.c b/drivers/irqchip/irq-gic-acpi.c index 58f7831..f9f1fc7 100644 --- a/drivers/irqchip/irq-gic-acpi.c +++ b/drivers/irqchip/irq-gic-acpi.c @@ -110,3 +110,32 @@ static int __init acpi_gic_version_init(void) return 0; } + +/* + * This special acpi_table_id is the sentinel at the end of the + * acpi_table_id[] array of all irqchips. It is automatically placed at + * the end of the array by the linker, thanks to being part of a + * special section. + */ +static const struct acpi_table_id +irqchip_acpi_match_end __used __section(__irqchip_acpi_table_end); + +extern struct acpi_table_id __irqchip_acpi_table[]; + +void __init acpi_irqchip_init(void) +{ + struct acpi_table_id *id; + + if (acpi_disabled) + return; + + if (acpi_gic_version_init()) + return; + + /* scan the irqchip table to match the GIC version and its driver */ + for (id = __irqchip_acpi_table; id->id[0]; id++) { + if (gic_version == (u8)id->driver_data) + acpi_table_parse(id->id, + (acpi_tbl_table_handler)id->handler); + } +} diff --git a/drivers/irqchip/irqchip.h b/drivers/irqchip/irqchip.h index 0f6486d..241d5f8 100644 --- a/drivers/irqchip/irqchip.h +++ b/drivers/irqchip/irqchip.h @@ -11,6 +11,7 @@ #ifndef _IRQCHIP_H #define _IRQCHIP_H +#include #include /* @@ -25,4 +26,15 @@ */ #define IRQCHIP_DECLARE(name, compat, fn) OF_DECLARE_2(irqchip, name, compat, fn) +/* + * This macro must be used by the different ARM GIC drivers to declare + * the association between their version and their initialization function. + * + * @name: name that must be unique accross all IRQCHIP_ACPI_DECLARE of the + * same file. + * @gic_version: version of GIC + * @fn: initialization function + */ +#define IRQCHIP_ACPI_DECLARE(name, gic_version, fn) \ + ACPI_DECLARE(irqchip, name, ACPI_SIG_MADT, gic_version, fn) #endif diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index 8bd374d..625776c 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -181,6 +181,18 @@ #define CPUIDLE_METHOD_OF_TABLES() OF_TABLE(CONFIG_CPU_IDLE, cpuidle_method) #define EARLYCON_OF_TABLES() OF_TABLE(CONFIG_SERIAL_EARLYCON, earlycon) +#ifdef CONFIG_ACPI +#define ACPI_TABLE(name) \ + . = ALIGN(8); \ + VMLINUX_SYMBOL(__##name##_acpi_table) = .; \ + *(__##name##_acpi_table) \ + *(__##name##_acpi_table_end) + +#define IRQCHIP_ACPI_MATCH_TABLE() ACPI_TABLE(irqchip) +#else +#define IRQCHIP_ACPI_MATCH_TABLE() +#endif + #define KERNEL_DTB() \ STRUCT_ALIGN(); \ VMLINUX_SYMBOL(__dtb_start) = .; \ @@ -516,6 +528,7 @@ CPUIDLE_METHOD_OF_TABLES() \ KERNEL_DTB() \ IRQCHIP_OF_MATCH_TABLE() \ + IRQCHIP_ACPI_MATCH_TABLE() \ EARLYCON_TABLE() \ EARLYCON_OF_TABLES() diff --git a/include/linux/acpi.h b/include/linux/acpi.h index caead48..d383e12 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -825,4 +825,20 @@ static inline struct acpi_device *acpi_get_next_child(struct device *dev, #endif +#ifdef CONFIG_ACPI +#define ACPI_DECLARE(table, name, table_id, data, fn) \ + static const struct acpi_table_id __acpi_table_##name \ + __used __section(__##table##_acpi_table) \ + = { .id = table_id, \ + .handler = (void *)fn, \ + .driver_data = data } +#else +#define ACPI_DECLARE(table, name, table_id, data, fn) \ + static const struct acpi_table_id __acpi_table_##name \ + __attribute__((unused)) \ + = { .id = table_id, \ + .handler = (void *)fn, \ + .driver_data = data } +#endif + #endif /*_LINUX_ACPI_H*/ diff --git a/include/linux/mod_devicetable.h b/include/linux/mod_devicetable.h index 3bfd567..c7fefc7 100644 --- a/include/linux/mod_devicetable.h +++ b/include/linux/mod_devicetable.h @@ -191,6 +191,14 @@ struct acpi_device_id { kernel_ulong_t driver_data; }; +#define ACPI_TABLE_ID_LEN 5 + +struct acpi_table_id { + __u8 id[ACPI_TABLE_ID_LEN]; + const void *handler; + kernel_ulong_t driver_data; +}; + #define PNP_ID_LEN 8 #define PNP_MAX_DEVICES 8 -- 1.9.1 -- 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/