1 #include <asm/byteorder.h> 2 #include "vphn.h" 3 4 /* 5 * The associativity domain numbers are returned from the hypervisor as a 6 * stream of mixed 16-bit and 32-bit fields. The stream is terminated by the 7 * special value of "all ones" (aka. 0xffff) and its size may not exceed 48 8 * bytes. 9 * 10 * --- 16-bit fields --> 11 * _________________________ 12 * | 0 | 1 | 2 | 3 | be_packed[0] 13 * ------+-----+-----+------ 14 * _________________________ 15 * | 4 | 5 | 6 | 7 | be_packed[1] 16 * ------------------------- 17 * ... 18 * _________________________ 19 * | 20 | 21 | 22 | 23 | be_packed[5] 20 * ------------------------- 21 * 22 * Convert to the sequence they would appear in the ibm,associativity property. 23 */ vphn_unpack_associativity(const long * packed,__be32 * unpacked)24int vphn_unpack_associativity(const long *packed, __be32 *unpacked) 25 { 26 __be64 be_packed[VPHN_REGISTER_COUNT]; 27 int i, nr_assoc_doms = 0; 28 const __be16 *field = (const __be16 *) be_packed; 29 u16 last = 0; 30 bool is_32bit = false; 31 32 #define VPHN_FIELD_UNUSED (0xffff) 33 #define VPHN_FIELD_MSB (0x8000) 34 #define VPHN_FIELD_MASK (~VPHN_FIELD_MSB) 35 36 /* Let's fix the values returned by plpar_hcall9() */ 37 for (i = 0; i < VPHN_REGISTER_COUNT; i++) 38 be_packed[i] = cpu_to_be64(packed[i]); 39 40 for (i = 1; i < VPHN_ASSOC_BUFSIZE; i++) { 41 u16 new = be16_to_cpup(field++); 42 43 if (is_32bit) { 44 /* Let's concatenate the 16 bits of this field to the 45 * 15 lower bits of the previous field 46 */ 47 unpacked[++nr_assoc_doms] = 48 cpu_to_be32(last << 16 | new); 49 is_32bit = false; 50 } else if (new == VPHN_FIELD_UNUSED) 51 /* This is the list terminator */ 52 break; 53 else if (new & VPHN_FIELD_MSB) { 54 /* Data is in the lower 15 bits of this field */ 55 unpacked[++nr_assoc_doms] = 56 cpu_to_be32(new & VPHN_FIELD_MASK); 57 } else { 58 /* Data is in the lower 15 bits of this field 59 * concatenated with the next 16 bit field 60 */ 61 last = new; 62 is_32bit = true; 63 } 64 } 65 66 /* The first cell contains the length of the property */ 67 unpacked[0] = cpu_to_be32(nr_assoc_doms); 68 69 return nr_assoc_doms; 70 } 71