From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752152Ab0FLSzb (ORCPT ); Sat, 12 Jun 2010 14:55:31 -0400 Received: from mail-wy0-f174.google.com ([74.125.82.174]:37579 "EHLO mail-wy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751805Ab0FLSz3 (ORCPT ); Sat, 12 Jun 2010 14:55:29 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=sender:from:date:subject:mime-version:x-tuid:x-uid:x-length:to :reply-to:content-type:content-transfer-encoding:message-id; b=iDYY00i2Hi1ll3XMZtgJDEwtrpg3dRDvZqrEOdbnOv80wduapu9OVq04lk4Ws28pB4 qXZEd+/p2xMi0tZSGihFuNjHGVB86bJ+ywb2pxW3bPU17BYOIEyDFncEDHAMdEV97h1O Fn4FfRmffZxbRICZTxgeVlmLZvqnkxxVc/BWs= From: Florian Fainelli Date: Sat, 12 Jun 2010 20:55:27 +0200 Subject: [PATCH v3] x86: CPU id detection for RDC System-on-Chip MIME-Version: 1.0 X-TUID: e82d9ebe12d64797 X-Length: 6795 To: mingo@elte.hu, "linux-kernel" Reply-To: Florian Fainelli Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <201006122055.28489.florian@openwrt.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Mark Kelly The RDC System-on-Chip i486 compatible core does not support the cpuid instruction and specific detection logic is required for this chip. The patch below adds proper vendor and SoC type detection. Signed-off-by: Mark Kelly Tested-by: Florian Fainelli --- diff --git a/Documentation/x86/rdc.txt b/Documentation/x86/rdc.txt new file mode 100644 index 0000000..f3dc7cf --- /dev/null +++ b/Documentation/x86/rdc.txt @@ -0,0 +1,67 @@ + +Introduction +============ + +RDC (http://www.rdc.com.tw) have been manufacturing x86-compatible SoC +(system-on-chips) for a number of years. They are not the fastest of +CPUs (clock speeds ranging from 133-150MHz) but 486SX compatibility +coupled with very low power consumption[1] and low cost make them ideal +for embedded applications. + + +Where to find +============= + +RDC chips show up in numerous embedded devices, but be careful since +many of them will not run Linux 2.6 without significant expertise. + +There are several variants of what the linux kernel refers to generically +as RDC321X: R8610, R321x, S3282 and AMRISC20000. + +R321x: Found in various routers, see the OpenWrt project for details, + http://wiki.openwrt.org/oldwiki/rdcport + +R8610: Found on the RDC evaluation board + http://www.ivankuten.com/system-on-chip-soc/rdc-r8610/ + +AMRISC20000: Found in the MGB-100 wireless hard disk + http://tintuc.no-ip.com/linux/tipps/mgb100/ + +S3282: Found in various NAS devices, including the Bifferboard + http://www.bifferos.com + + +Kernel Configuration +==================== + +Add support for this CPU with CONFIG_X86_RDC321X. Ensure that maths +emulation is included (CONFIG_MATH_EMULATION selected) and avoid MCE +(CONFIG_X86_MCE not selected). + + +CPU detection +============= + +None of these chips support the cpuid instruction, so as with some +other x86 compatible SoCs, we must check the north bridge and look +for specific 'signature' PCI device config. + +If you run a kernel on an unsupported customer id device, please file +a bug with your customer id to: http://bugzilla.kernel.org/. + +Credits +======= + +Many thanks to RDC for providing the customer codes to allow +detection of all known variants, without which this detection code +would have been very hard to ascertain. + + +References +========== + +[1] S3282 in certain NAS solutions consumes less than 1W + + +mark@bifferos.com 2009 + diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 6f77afa..4387451 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -422,6 +422,7 @@ config X86_RDC321X bool "RDC R-321x SoC" depends on X86_32 depends on X86_EXTENDED_PLATFORM + select PCI select M486 select X86_REBOOTFIXUPS ---help--- diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index 7e5c6a6..c72d99d 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -122,7 +122,8 @@ struct cpuinfo_x86 { #define X86_VENDOR_CENTAUR 5 #define X86_VENDOR_TRANSMETA 7 #define X86_VENDOR_NSC 8 -#define X86_VENDOR_NUM 9 +#define X86_VENDOR_RDC 9 +#define X86_VENDOR_NUM 10 #define X86_VENDOR_UNKNOWN 0xff diff --git a/arch/x86/kernel/cpu/Makefile b/arch/x86/kernel/cpu/Makefile index 3a785da..af2d4a6 100644 --- a/arch/x86/kernel/cpu/Makefile +++ b/arch/x86/kernel/cpu/Makefile @@ -25,6 +25,7 @@ obj-$(CONFIG_CPU_SUP_CYRIX_32) += cyrix.o obj-$(CONFIG_CPU_SUP_CENTAUR) += centaur.o obj-$(CONFIG_CPU_SUP_TRANSMETA_32) += transmeta.o obj-$(CONFIG_CPU_SUP_UMC_32) += umc.o +obj-$(CONFIG_X86_RDC321X) += rdc.o obj-$(CONFIG_PERF_EVENTS) += perf_event.o diff --git a/arch/x86/kernel/cpu/rdc.c b/arch/x86/kernel/cpu/rdc.c new file mode 100644 index 0000000..c2bcdcc --- /dev/null +++ b/arch/x86/kernel/cpu/rdc.c @@ -0,0 +1,73 @@ +/* + * See Documentation/x86/rdc.txt + * + * mark@bifferos.com + */ + +#include +#include +#include "cpu.h" + + +static void __cpuinit rdc_identify(struct cpuinfo_x86 *c) +{ + u32 id; + u16 vendor, device; + u32 customer_id; + + if (!early_pci_allowed()) + return; + + /* RDC CPU is SoC (system-on-chip), Northbridge is always present */ + id = read_pci_config(0, 0, 0, PCI_VENDOR_ID); + vendor = id & 0xffff; + device = (id >> 16) & 0xffff; + + if (vendor != PCI_VENDOR_ID_RDC || device != PCI_DEVICE_ID_RDC_R6020) + return; /* not RDC */ + /* + * NB: We could go on and check other devices, e.g. r6040 NIC, but + * that's probably overkill + */ + + customer_id = read_pci_config(0, 0, 0, 0x90); + + switch (customer_id) { + /* id names are from RDC */ + case 0x00321000: + strcpy(c->x86_model_id, "R3210/R3211"); + break; + case 0x00321001: + strcpy(c->x86_model_id, "AMITRISC20000/20010"); + break; + case 0x00321002: + strcpy(c->x86_model_id, "R3210X/Edimax"); + break; + case 0x00321003: + strcpy(c->x86_model_id, "R3210/Kcodes"); + break; + case 0x00321004: /* tested */ + strcpy(c->x86_model_id, "S3282/CodeTek"); + break; + case 0x00321007: + strcpy(c->x86_model_id, "R8610"); + break; + default: + pr_info("RDC CPU: Unrecognised Customer ID (0x%x) please " + "report to: http://bugzilla.kernel.org/\n", + customer_id); + break; + } + + strcpy(c->x86_vendor_id, "RDC"); + c->x86_vendor = X86_VENDOR_RDC; +} + +static const struct cpu_dev __cpuinitconst rdc_cpu_dev = { + .c_vendor = "RDC", + .c_ident = { "RDC" }, + .c_identify = rdc_identify, + .c_x86_vendor = X86_VENDOR_RDC, +}; + +cpu_dev_register(rdc_cpu_dev);