From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- arch/powerpc/mm/vphn.c | 70 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 70 insertions(+) create mode 100644 arch/powerpc/mm/vphn.c (limited to 'arch/powerpc/mm/vphn.c') diff --git a/arch/powerpc/mm/vphn.c b/arch/powerpc/mm/vphn.c new file mode 100644 index 000000000..5f8ef50e5 --- /dev/null +++ b/arch/powerpc/mm/vphn.c @@ -0,0 +1,70 @@ +#include +#include "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. + */ +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; +} -- cgit v1.2.3-54-g00ecf