1dbf4ed89SMax Filippov/* SPDX-License-Identifier: GPL-2.0-or-later WITH GCC-exception-2.0 */ 2dbf4ed89SMax Filippov#include <linux/linkage.h> 3dbf4ed89SMax Filippov#include <asm/asmmacro.h> 4dbf4ed89SMax Filippov#include <asm/core.h> 5dbf4ed89SMax Filippov 6dbf4ed89SMax FilippovENTRY(__udivsi3) 7dbf4ed89SMax Filippov 8dbf4ed89SMax Filippov abi_entry_default 9dbf4ed89SMax Filippov#if XCHAL_HAVE_DIV32 10dbf4ed89SMax Filippov quou a2, a2, a3 11dbf4ed89SMax Filippov#else 12dbf4ed89SMax Filippov bltui a3, 2, .Lle_one /* check if the divisor <= 1 */ 13dbf4ed89SMax Filippov 14dbf4ed89SMax Filippov mov a6, a2 /* keep dividend in a6 */ 15dbf4ed89SMax Filippov do_nsau a5, a6, a2, a7 /* dividend_shift = nsau (dividend) */ 16dbf4ed89SMax Filippov do_nsau a4, a3, a2, a7 /* divisor_shift = nsau (divisor) */ 17dbf4ed89SMax Filippov bgeu a5, a4, .Lspecial 18dbf4ed89SMax Filippov 19dbf4ed89SMax Filippov sub a4, a4, a5 /* count = divisor_shift - dividend_shift */ 20dbf4ed89SMax Filippov ssl a4 21dbf4ed89SMax Filippov sll a3, a3 /* divisor <<= count */ 22dbf4ed89SMax Filippov movi a2, 0 /* quotient = 0 */ 23dbf4ed89SMax Filippov 24dbf4ed89SMax Filippov /* test-subtract-and-shift loop; one quotient bit on each iteration */ 25dbf4ed89SMax Filippov#if XCHAL_HAVE_LOOPS 26dbf4ed89SMax Filippov loopnez a4, .Lloopend 27dbf4ed89SMax Filippov#endif /* XCHAL_HAVE_LOOPS */ 28dbf4ed89SMax Filippov.Lloop: 29dbf4ed89SMax Filippov bltu a6, a3, .Lzerobit 30dbf4ed89SMax Filippov sub a6, a6, a3 31dbf4ed89SMax Filippov addi a2, a2, 1 32dbf4ed89SMax Filippov.Lzerobit: 33dbf4ed89SMax Filippov slli a2, a2, 1 34dbf4ed89SMax Filippov srli a3, a3, 1 35dbf4ed89SMax Filippov#if !XCHAL_HAVE_LOOPS 36dbf4ed89SMax Filippov addi a4, a4, -1 37dbf4ed89SMax Filippov bnez a4, .Lloop 38dbf4ed89SMax Filippov#endif /* !XCHAL_HAVE_LOOPS */ 39dbf4ed89SMax Filippov.Lloopend: 40dbf4ed89SMax Filippov 41dbf4ed89SMax Filippov bltu a6, a3, .Lreturn 42dbf4ed89SMax Filippov addi a2, a2, 1 /* increment quotient if dividend >= divisor */ 43dbf4ed89SMax Filippov.Lreturn: 44dbf4ed89SMax Filippov abi_ret_default 45dbf4ed89SMax Filippov 46dbf4ed89SMax Filippov.Lle_one: 47dbf4ed89SMax Filippov beqz a3, .Lerror /* if divisor == 1, return the dividend */ 48dbf4ed89SMax Filippov abi_ret_default 49dbf4ed89SMax Filippov 50dbf4ed89SMax Filippov.Lspecial: 51dbf4ed89SMax Filippov /* return dividend >= divisor */ 52dbf4ed89SMax Filippov bltu a6, a3, .Lreturn0 53dbf4ed89SMax Filippov movi a2, 1 54dbf4ed89SMax Filippov abi_ret_default 55dbf4ed89SMax Filippov 56dbf4ed89SMax Filippov.Lerror: 57dbf4ed89SMax Filippov /* Divide by zero: Use an illegal instruction to force an exception. 58dbf4ed89SMax Filippov The subsequent "DIV0" string can be recognized by the exception 59dbf4ed89SMax Filippov handler to identify the real cause of the exception. */ 60dbf4ed89SMax Filippov ill 61dbf4ed89SMax Filippov .ascii "DIV0" 62dbf4ed89SMax Filippov 63dbf4ed89SMax Filippov.Lreturn0: 64dbf4ed89SMax Filippov movi a2, 0 65dbf4ed89SMax Filippov#endif /* XCHAL_HAVE_DIV32 */ 66dbf4ed89SMax Filippov abi_ret_default 67dbf4ed89SMax Filippov 68dbf4ed89SMax FilippovENDPROC(__udivsi3) 69*338d9150SMax FilippovEXPORT_SYMBOL(__udivsi3) 70