| // SPDX-License-Identifier: GPL-2.0 | |
| #include <asm/byteorder.h> | |
| #include <asm/vphn.h> | |
| /* | |
| * The associativity domain numbers are returned from the hypervisor as a | |
| * stream of mixed 16-bit and 32-bit fields. The stream is terminated by the | |
| * special value of "all ones" (aka. 0xffff) and its size may not exceed 48 | |
| * bytes. | |
| * | |
| * --- 16-bit fields --> | |
| * _________________________ | |
| * | 0 | 1 | 2 | 3 | be_packed[0] | |
| * ------+-----+-----+------ | |
| * _________________________ | |
| * | 4 | 5 | 6 | 7 | be_packed[1] | |
| * ------------------------- | |
| * ... | |
| * _________________________ | |
| * | 20 | 21 | 22 | 23 | be_packed[5] | |
| * ------------------------- | |
| * | |
| * Convert to the sequence they would appear in the ibm,associativity property. | |
| */ | |
| static int vphn_unpack_associativity(const long *packed, __be32 *unpacked) | |
| { | |
| __be64 be_packed[VPHN_REGISTER_COUNT]; | |
| int i, nr_assoc_doms = 0; | |
| const __be16 *field = (const __be16 *) be_packed; | |
| u16 last = 0; | |
| bool is_32bit = false; | |
| #define VPHN_FIELD_UNUSED (0xffff) | |
| #define VPHN_FIELD_MSB (0x8000) | |
| #define VPHN_FIELD_MASK (~VPHN_FIELD_MSB) | |
| /* Let's fix the values returned by plpar_hcall9() */ | |
| for (i = 0; i < VPHN_REGISTER_COUNT; i++) | |
| be_packed[i] = cpu_to_be64(packed[i]); | |
| for (i = 1; i < VPHN_ASSOC_BUFSIZE; i++) { | |
| u16 new = be16_to_cpup(field++); | |
| if (is_32bit) { | |
| /* | |
| * Let's concatenate the 16 bits of this field to the | |
| * 15 lower bits of the previous field | |
| */ | |
| unpacked[++nr_assoc_doms] = | |
| cpu_to_be32(last << 16 | new); | |
| is_32bit = false; | |
| } else if (new == VPHN_FIELD_UNUSED) | |
| /* This is the list terminator */ | |
| break; | |
| else if (new & VPHN_FIELD_MSB) { | |
| /* Data is in the lower 15 bits of this field */ | |
| unpacked[++nr_assoc_doms] = | |
| cpu_to_be32(new & VPHN_FIELD_MASK); | |
| } else { | |
| /* | |
| * Data is in the lower 15 bits of this field | |
| * concatenated with the next 16 bit field | |
| */ | |
| last = new; | |
| is_32bit = true; | |
| } | |
| } | |
| /* The first cell contains the length of the property */ | |
| unpacked[0] = cpu_to_be32(nr_assoc_doms); | |
| return nr_assoc_doms; | |
| } | |
| /* NOTE: This file is included by a selftest and built in userspace. */ | |
| #ifdef __KERNEL__ | |
| #include <asm/hvcall.h> | |
| long hcall_vphn(unsigned long cpu, u64 flags, __be32 *associativity) | |
| { | |
| long rc; | |
| long retbuf[PLPAR_HCALL9_BUFSIZE] = {0}; | |
| rc = plpar_hcall9(H_HOME_NODE_ASSOCIATIVITY, retbuf, flags, cpu); | |
| if (rc == H_SUCCESS) | |
| vphn_unpack_associativity(retbuf, associativity); | |
| return rc; | |
| } | |
| #endif |