> Date: Fri, 13 Jul 2012 14:57:11 +0200
> From: "Christiano F. Haesbaert" <haesba...@openbsd.org>
>
> Ok so here is the version with #ifndef SMALL_KERNEL, the only question
> that remains is: do we keep the printf in dmesg ? or shall I take that
> out ?
>
> I'd like to keep it so we may know if the detection is correctly just by
> looking at sent dmesgs.
Can you shelve this until you:
a) Have the equivalent code for i386.
b) Have something that actually uses this?
Cheers,
Mark
> Index: arch/amd64/amd64/identcpu.c
> ===================================================================
> RCS file: /cvs/src/sys/arch/amd64/amd64/identcpu.c,v
> retrieving revision 1.36
> diff -d -u -p -r1.36 identcpu.c
> --- arch/amd64/amd64/identcpu.c 22 Apr 2012 19:36:09 -0000 1.36
> +++ arch/amd64/amd64/identcpu.c 13 Jul 2012 11:45:58 -0000
> @@ -446,4 +446,126 @@ identifycpu(struct cpu_info *ci)
> sensordev_install(&ci->ci_sensordev);
> #endif
> }
> +#ifndef SMALL_KERNEL
> + cpu_topology(ci);
> +#endif
> +}
> +
> +#ifndef SMALL_KERNEL
> +/*
> + * Base 2 logarithm of an int. returns 0 for 0 (yeye, I know).
> + */
> +static int
> +log2(unsigned int i)
> +{
> + int ret = 0;
> +
> + while (i >>= 1)
> + ret++;
> +
> + return (ret);
> +}
> +
> +static int
> +mask_width(u_int x)
> +{
> + int bit;
> + int mask;
> + int powerof2;
> +
> + powerof2 = ((x - 1) & x) == 0;
> + mask = (x << (1 - powerof2)) - 1;
> +
> + /* fls */
> + if (mask == 0)
> + return (0);
> + for (bit = 1; mask != 1; bit++)
> + mask = (unsigned int)mask >> 1;
> +
> + return (bit);
> +}
> +
> +/*
> + * Build up cpu topology for given cpu, must run on the core itself.
> + */
> +void
> +cpu_topology(struct cpu_info *ci)
> +{
> + u_int32_t eax, ebx, ecx, edx;
> + u_int32_t apicid, max_apicid, max_coreid;
> + u_int32_t smt_bits, core_bits, pkg_bits;
> + u_int32_t smt_mask, core_mask, pkg_mask;
> +
> + /* We need at least apicid at CPUID 1 */
> + CPUID(0, eax, ebx, ecx, edx);
> + if (eax < 1)
> + goto no_topology;
> +
> + /* Initial apicid */
> + CPUID(1, eax, ebx, ecx, edx);
> + apicid = (ebx >> 24) & 0xff;
> +
> + if (strcmp(cpu_vendor, "AuthenticAMD") == 0) {
> + /* We need at least apicid at CPUID 0x80000008 */
> + CPUID(0x80000000, eax, ebx, ecx, edx);
> + if (eax < 0x80000008)
> + goto no_topology;
> +
> + CPUID(0x80000008, eax, ebx, ecx, edx);
> + core_bits = (ecx >> 12) & 0xf;
> + if (core_bits == 0)
> + goto no_topology;
> + /* So coreidsize 2 gives 3, 3 gives 7... */
> + core_mask = (1 << core_bits) - 1;
> + /* Core id is the least significant considering mask */
> + ci->ci_core_id = apicid & core_mask;
> + /* Pkg id is the upper remaining bits */
> + ci->ci_pkg_id = apicid & ~core_mask;
> + ci->ci_pkg_id >>= core_bits;
> + } else if (strcmp(cpu_vendor, "GenuineIntel") == 0) {
> + /* We only support leaf 1/4 detection */
> + CPUID(0, eax, ebx, ecx, edx);
> + if (eax < 4)
> + goto no_topology;
> + /* Get max_apicid */
> + CPUID(1, eax, ebx, ecx, edx);
> + max_apicid = (ebx >> 16) & 0xff;
> + /* Get max_coreid */
> + CPUID2(4, 0, eax, ebx, ecx, edx);
> + max_coreid = ((eax >> 26) & 0x3f) + 1;
> + /* SMT */
> + smt_bits = mask_width(max_apicid / max_coreid);
> + smt_mask = (1 << smt_bits) - 1;
> + /* Core */
> + core_bits = log2(max_coreid);
> + core_mask = (1 << (core_bits + smt_bits)) - 1;
> + core_mask ^= smt_mask;
> + /* Pkg */
> + pkg_bits = core_bits + smt_bits;
> + pkg_mask = -1 << core_bits;
> +
> + ci->ci_smt_id = apicid & smt_mask;
> + ci->ci_core_id = (apicid & core_mask) >> smt_bits;
> + ci->ci_pkg_id = (apicid & pkg_mask) >> pkg_bits;
> + } else
> + goto no_topology;
> +#ifdef DEBUG
> + printf("cpu%d: smt %u, core %u, pkg %u "
> + "(apicid 0x%x, max_apicid 0x%x, max_coreid 0x%x, smt_bits 0x%x,
> smt_mask 0x%x, "
> + "core_bits 0x%x, core_mask 0x%x, pkg_bits 0x%x, pkg_mask 0x%x)\n",
> + ci->ci_cpuid, ci->ci_smt_id, ci->ci_core_id, ci->ci_pkg_id,
> + apicid, max_apicid, max_coreid, smt_bits, smt_mask, core_bits,
> + core_mask, pkg_bits, pkg_mask);
> +#else
> + printf("cpu%d: smt %u, core %u, package %u\n", ci->ci_cpuid,
> + ci->ci_smt_id, ci->ci_core_id, ci->ci_pkg_id);
> +
> +#endif
> + return;
> + /* We can't map, so consider ci_core_id as ci_cpuid */
> +no_topology:
> + ci->ci_smt_id = 0;
> + ci->ci_core_id = ci->ci_cpuid;
> + ci->ci_pkg_id = 0;
> }
> +#endif /* SMALL_KERNEL */
> Index: arch/amd64/include/cpu.h
> ===================================================================
> RCS file: /cvs/src/sys/arch/amd64/include/cpu.h,v
> retrieving revision 1.73
> diff -d -u -p -r1.73 cpu.h
> --- arch/amd64/include/cpu.h 17 Apr 2012 16:02:33 -0000 1.73
> +++ arch/amd64/include/cpu.h 13 Jul 2012 11:56:34 -0000
> @@ -100,7 +100,11 @@ struct cpu_info {
> u_int32_t ci_model;
> u_int32_t ci_cflushsz;
> u_int64_t ci_tsc_freq;
> -
> +#ifndef SMALL_KERNEL
> + u_int32_t ci_smt_id;
> + u_int32_t ci_core_id;
> + u_int32_t ci_pkg_id;
> +#endif /* SMALL_KERNEL */
> struct cpu_functions *ci_func;
> void (*cpu_setup)(struct cpu_info *);
> void (*ci_info)(struct cpu_info *);
> @@ -266,6 +270,9 @@ extern int cpuspeed;
> /* identcpu.c */
> void identifycpu(struct cpu_info *);
> int cpu_amd64speed(int *);
> +#ifndef SMALL_KERNEL
> +void cpu_topology(struct cpu_info *);
> +#endif /* SMALL_KERNEL */
>
> /* machdep.c */
> void dumpconf(void);
> Index: arch/amd64/include/specialreg.h
> ===================================================================
> RCS file: /cvs/src/sys/arch/amd64/include/specialreg.h,v
> retrieving revision 1.21
> diff -d -u -p -r1.21 specialreg.h
> --- arch/amd64/include/specialreg.h 27 Mar 2012 05:59:46 -0000 1.21
> +++ arch/amd64/include/specialreg.h 13 Jul 2012 11:26:24 -0000
> @@ -187,11 +187,13 @@
> #define CPUID2MODEL(cpuid) (((cpuid) >> 4) & 15)
> #define CPUID2STEPPING(cpuid) ((cpuid) & 15)
>
> -#define CPUID(code, eax, ebx, ecx, edx) \
> +#define CPUID2(eax_code, ecx_code, eax, ebx, ecx, edx) \
> __asm("cpuid" \
> : "=a" (eax), "=b" (ebx), "=c" (ecx), "=d" (edx) \
> - : "a" (code));
> + : "a" (eax_code), "c" (ecx_code));
>
> +#define CPUID(code, eax, ebx, ecx, edx) \
> + CPUID2(code, 0, eax, ebx, ecx, edx)
>
> /*
> * Model-specific registers for the i386 family
