2 +++ b/Documentation/x86/rdc.txt
8 +RDC (http://www.rdc.com.tw) have been manufacturing x86-compatible SoC
9 +(system-on-chips) for a number of years. They are not the fastest of
10 +CPUs (clock speeds ranging from 133-150MHz) but 486SX compatibility
11 +coupled with very low power consumption[1] and low cost make them ideal
12 +for embedded applications.
18 +RDC chips show up in numerous embedded devices, but be careful since
19 +many of them will not run Linux 2.6 without significant expertise.
21 +There are several variants of what the linux kernel refers to generically
22 +as RDC321X: R8610, R321x, S3282 and AMRISC20000.
24 +R321x: Found in various routers, see the OpenWrt project for details,
25 + http://wiki.openwrt.org/oldwiki/rdcport
27 +R8610: Found on the RDC evaluation board
28 + http://www.ivankuten.com/system-on-chip-soc/rdc-r8610/
30 +AMRISC20000: Found in the MGB-100 wireless hard disk
31 + http://tintuc.no-ip.com/linux/tipps/mgb100/
33 +S3282: Found in various NAS devices, including the Bifferboard
34 + http://www.bifferos.com
40 +Add support for this CPU with CONFIG_X86_RDC321X. Ensure that maths
41 +emulation is included (CONFIG_MATH_EMULATION selected) and avoid MCE
42 +(CONFIG_X86_MCE not selected).
48 +None of these chips support the cpuid instruction, so as with some
49 +other x86 compatible SoCs, we must check the north bridge and look
50 +for specific 'signature' PCI device config.
52 +The current detection code has been tested only on the Bifferboard
53 +(S3282 CPU), please send bug reports or success stories with
54 +other devices to bifferos@yahoo.co.uk.
60 +Many thanks to RDC for providing the customer codes to allow
61 +detection of all known variants, without which this detection code
62 +would have been very hard to ascertain.
68 +[1] S3282 in certain NAS solutions consumes less than 1W
71 +mark@bifferos.com 2009
73 --- a/arch/x86/Kconfig
74 +++ b/arch/x86/Kconfig
75 @@ -378,6 +378,7 @@ config X86_RDC321X
78 depends on X86_EXTENDED_PLATFORM
81 select X86_REBOOTFIXUPS
83 --- a/arch/x86/include/asm/processor.h
84 +++ b/arch/x86/include/asm/processor.h
85 @@ -121,7 +121,8 @@ struct cpuinfo_x86 {
86 #define X86_VENDOR_CENTAUR 5
87 #define X86_VENDOR_TRANSMETA 7
88 #define X86_VENDOR_NSC 8
89 -#define X86_VENDOR_NUM 9
90 +#define X86_VENDOR_RDC 9
91 +#define X86_VENDOR_NUM 10
93 #define X86_VENDOR_UNKNOWN 0xff
95 --- a/arch/x86/kernel/cpu/Makefile
96 +++ b/arch/x86/kernel/cpu/Makefile
97 @@ -22,6 +22,7 @@ obj-$(CONFIG_CPU_SUP_CYRIX_32) += cyrix
98 obj-$(CONFIG_CPU_SUP_CENTAUR) += centaur.o
99 obj-$(CONFIG_CPU_SUP_TRANSMETA_32) += transmeta.o
100 obj-$(CONFIG_CPU_SUP_UMC_32) += umc.o
101 +obj-$(CONFIG_X86_RDC321X) += rdc.o
103 obj-$(CONFIG_X86_MCE) += mcheck/
104 obj-$(CONFIG_MTRR) += mtrr/
106 +++ b/arch/x86/kernel/cpu/rdc.c
109 + * See Documentation/x86/rdc.txt
111 + * mark@bifferos.com
114 +#include <linux/pci.h>
115 +#include <asm/pci-direct.h>
119 +static void __cpuinit rdc_identify(struct cpuinfo_x86 *c)
121 + u16 vendor, device;
124 + if (!early_pci_allowed())
127 + /* RDC CPU is SoC (system-on-chip), Northbridge is always present */
128 + vendor = read_pci_config_16(0, 0, 0, PCI_VENDOR_ID);
129 + device = read_pci_config_16(0, 0, 0, PCI_DEVICE_ID);
131 + if (vendor != PCI_VENDOR_ID_RDC || device != PCI_DEVICE_ID_RDC_R6020)
132 + return; /* not RDC */
134 + * NB: We could go on and check other devices, e.g. r6040 NIC, but
135 + * that's probably overkill
138 + customer_id = read_pci_config(0, 0, 0, 0x90);
140 + switch (customer_id) {
141 + /* id names are from RDC */
143 + strcpy(c->x86_model_id, "R3210/R3211");
146 + strcpy(c->x86_model_id, "AMITRISC20000/20010");
149 + strcpy(c->x86_model_id, "R3210X/Edimax");
152 + strcpy(c->x86_model_id, "R3210/Kcodes");
154 + case 0x00321004: /* tested */
155 + strcpy(c->x86_model_id, "S3282/CodeTek");
158 + strcpy(c->x86_model_id, "R8610");
161 + pr_info("RDC CPU: Unrecognised Customer ID (0x%x) please report to linux-kernel@vger.kernel.org\n", customer_id);
165 + strcpy(c->x86_vendor_id, "RDC");
166 + c->x86_vendor = X86_VENDOR_RDC;
169 +static const struct cpu_dev __cpuinitconst rdc_cpu_dev = {
171 + .c_ident = { "RDC" },
172 + .c_identify = rdc_identify,
173 + .c_x86_vendor = X86_VENDOR_RDC,
176 +cpu_dev_register(rdc_cpu_dev);