162306a36Sopenharmony_ci/* SPDX-License-Identifier: GPL-2.0-or-later WITH GCC-exception-2.0 */ 262306a36Sopenharmony_ci#include <linux/linkage.h> 362306a36Sopenharmony_ci#include <asm/asmmacro.h> 462306a36Sopenharmony_ci#include <asm/core.h> 562306a36Sopenharmony_ci 662306a36Sopenharmony_ciENTRY(__udivsi3) 762306a36Sopenharmony_ci 862306a36Sopenharmony_ci abi_entry_default 962306a36Sopenharmony_ci#if XCHAL_HAVE_DIV32 1062306a36Sopenharmony_ci quou a2, a2, a3 1162306a36Sopenharmony_ci#else 1262306a36Sopenharmony_ci bltui a3, 2, .Lle_one /* check if the divisor <= 1 */ 1362306a36Sopenharmony_ci 1462306a36Sopenharmony_ci mov a6, a2 /* keep dividend in a6 */ 1562306a36Sopenharmony_ci do_nsau a5, a6, a2, a7 /* dividend_shift = nsau (dividend) */ 1662306a36Sopenharmony_ci do_nsau a4, a3, a2, a7 /* divisor_shift = nsau (divisor) */ 1762306a36Sopenharmony_ci bgeu a5, a4, .Lspecial 1862306a36Sopenharmony_ci 1962306a36Sopenharmony_ci sub a4, a4, a5 /* count = divisor_shift - dividend_shift */ 2062306a36Sopenharmony_ci ssl a4 2162306a36Sopenharmony_ci sll a3, a3 /* divisor <<= count */ 2262306a36Sopenharmony_ci movi a2, 0 /* quotient = 0 */ 2362306a36Sopenharmony_ci 2462306a36Sopenharmony_ci /* test-subtract-and-shift loop; one quotient bit on each iteration */ 2562306a36Sopenharmony_ci#if XCHAL_HAVE_LOOPS 2662306a36Sopenharmony_ci loopnez a4, .Lloopend 2762306a36Sopenharmony_ci#endif /* XCHAL_HAVE_LOOPS */ 2862306a36Sopenharmony_ci.Lloop: 2962306a36Sopenharmony_ci bltu a6, a3, .Lzerobit 3062306a36Sopenharmony_ci sub a6, a6, a3 3162306a36Sopenharmony_ci addi a2, a2, 1 3262306a36Sopenharmony_ci.Lzerobit: 3362306a36Sopenharmony_ci slli a2, a2, 1 3462306a36Sopenharmony_ci srli a3, a3, 1 3562306a36Sopenharmony_ci#if !XCHAL_HAVE_LOOPS 3662306a36Sopenharmony_ci addi a4, a4, -1 3762306a36Sopenharmony_ci bnez a4, .Lloop 3862306a36Sopenharmony_ci#endif /* !XCHAL_HAVE_LOOPS */ 3962306a36Sopenharmony_ci.Lloopend: 4062306a36Sopenharmony_ci 4162306a36Sopenharmony_ci bltu a6, a3, .Lreturn 4262306a36Sopenharmony_ci addi a2, a2, 1 /* increment quotient if dividend >= divisor */ 4362306a36Sopenharmony_ci.Lreturn: 4462306a36Sopenharmony_ci abi_ret_default 4562306a36Sopenharmony_ci 4662306a36Sopenharmony_ci.Lle_one: 4762306a36Sopenharmony_ci beqz a3, .Lerror /* if divisor == 1, return the dividend */ 4862306a36Sopenharmony_ci abi_ret_default 4962306a36Sopenharmony_ci 5062306a36Sopenharmony_ci.Lspecial: 5162306a36Sopenharmony_ci /* return dividend >= divisor */ 5262306a36Sopenharmony_ci bltu a6, a3, .Lreturn0 5362306a36Sopenharmony_ci movi a2, 1 5462306a36Sopenharmony_ci abi_ret_default 5562306a36Sopenharmony_ci 5662306a36Sopenharmony_ci.Lerror: 5762306a36Sopenharmony_ci /* Divide by zero: Use an illegal instruction to force an exception. 5862306a36Sopenharmony_ci The subsequent "DIV0" string can be recognized by the exception 5962306a36Sopenharmony_ci handler to identify the real cause of the exception. */ 6062306a36Sopenharmony_ci ill 6162306a36Sopenharmony_ci .ascii "DIV0" 6262306a36Sopenharmony_ci 6362306a36Sopenharmony_ci.Lreturn0: 6462306a36Sopenharmony_ci movi a2, 0 6562306a36Sopenharmony_ci#endif /* XCHAL_HAVE_DIV32 */ 6662306a36Sopenharmony_ci abi_ret_default 6762306a36Sopenharmony_ci 6862306a36Sopenharmony_ciENDPROC(__udivsi3) 6962306a36Sopenharmony_ciEXPORT_SYMBOL(__udivsi3) 70