From: Leon Alrae Date: Wed, 24 Feb 2016 10:47:10 +0000 (+0000) Subject: target-mips: indicate presence of IEEE 754-2008 FPU in R6/R5+MSA CPUs X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=ba5c79f26221c0fd7139c883a34a4e75d993f732;p=qmiga%2Fqemu.git target-mips: indicate presence of IEEE 754-2008 FPU in R6/R5+MSA CPUs MIPS Release 6 and MIPS SIMD Architecture make it mandatory to have IEEE 754-2008 FPU which is indicated by CP1 FIR.HAS2008, FCSR.ABS2008 and FCSR.NAN2008 bits set to 1. In QEMU we still keep these bits cleared as there is no 2008-NaN support. However, this now causes problems preventing from running R6 Linux with the v4.5 kernel. Kernel refuses to execute 2008-NaN ELFs on a CPU whose FPU does not support 2008-NaN encoding: (...) VFS: Mounted root (ext4 filesystem) readonly on device 8:0. devtmpfs: mounted Freeing unused kernel memory: 256K (ffffffff806f0000 - ffffffff80730000) request_module: runaway loop modprobe binfmt-464c Starting init: /sbin/init exists but couldn't execute it (error -8) request_module: runaway loop modprobe binfmt-464c Starting init: /bin/sh exists but couldn't execute it (error -8) Kernel panic - not syncing: No working init found. Try passing init= option to kernel. See Linux Documentation/init.txt for guidance. Therefore always indicate presence of 2008-NaN support in R6 as well as in R5+MSA CPUs, even though this feature is not yet supported by MIPS in QEMU. Signed-off-by: Leon Alrae --- diff --git a/target-mips/cpu.h b/target-mips/cpu.h index 1e2b070cc3..4f3ebb9dbb 100644 --- a/target-mips/cpu.h +++ b/target-mips/cpu.h @@ -99,6 +99,7 @@ struct CPUMIPSFPUContext { uint32_t fcr0; #define FCR0_FREP 29 #define FCR0_UFRP 28 +#define FCR0_HAS2008 23 #define FCR0_F64 22 #define FCR0_L 21 #define FCR0_W 20 @@ -110,6 +111,8 @@ struct CPUMIPSFPUContext { #define FCR0_REV 0 /* fcsr */ uint32_t fcr31; +#define FCR31_ABS2008 19 +#define FCR31_NAN2008 18 #define SET_FP_COND(num,env) do { ((env).fcr31) |= ((num) ? (1 << ((num) + 24)) : (1 << 23)); } while(0) #define CLEAR_FP_COND(num,env) do { ((env).fcr31) &= ~((num) ? (1 << ((num) + 24)) : (1 << 23)); } while(0) #define GET_FP_COND(env) ((((env).fcr31 >> 24) & 0xfe) | (((env).fcr31 >> 23) & 0x1)) diff --git a/target-mips/translate.c b/target-mips/translate.c index 12ed8208d0..0f43bf4758 100644 --- a/target-mips/translate.c +++ b/target-mips/translate.c @@ -20012,6 +20012,7 @@ void cpu_state_reset(CPUMIPSState *env) env->CP0_PageGrain_rw_bitmask = env->cpu_model->CP0_PageGrain_rw_bitmask; env->CP0_PageGrain = env->cpu_model->CP0_PageGrain; env->active_fpu.fcr0 = env->cpu_model->CP1_fcr0; + env->active_fpu.fcr31 = env->cpu_model->CP1_fcr31; env->msair = env->cpu_model->MSAIR; env->insn_flags = env->cpu_model->insn_flags; diff --git a/target-mips/translate_init.c b/target-mips/translate_init.c index cdef59d952..3192db0960 100644 --- a/target-mips/translate_init.c +++ b/target-mips/translate_init.c @@ -84,6 +84,7 @@ struct mips_def_t { int32_t CP0_TCStatus_rw_bitmask; int32_t CP0_SRSCtl; int32_t CP1_fcr0; + int32_t CP1_fcr31; int32_t MSAIR; int32_t SEGBITS; int32_t PABITS; @@ -421,9 +422,10 @@ static const mips_def_t mips_defs[] = .CP0_Status_rw_bitmask = 0x3C68FF1F, .CP0_PageGrain_rw_bitmask = (1U << CP0PG_RIE) | (1 << CP0PG_XIE) | (1 << CP0PG_ELPA) | (1 << CP0PG_IEC), - .CP1_fcr0 = (1 << FCR0_FREP) | (1 << FCR0_UFRP) | (1 << FCR0_F64) | - (1 << FCR0_L) | (1 << FCR0_W) | (1 << FCR0_D) | - (1 << FCR0_S) | (0x03 << FCR0_PRID), + .CP1_fcr0 = (1 << FCR0_FREP) | (1 << FCR0_UFRP) | (1 << FCR0_HAS2008) | + (1 << FCR0_F64) | (1 << FCR0_L) | (1 << FCR0_W) | + (1 << FCR0_D) | (1 << FCR0_S) | (0x03 << FCR0_PRID), + .CP1_fcr31 = (1 << FCR31_ABS2008) | (1 << FCR31_NAN2008), .SEGBITS = 32, .PABITS = 40, .insn_flags = CPU_MIPS32R5 | ASE_MSA, @@ -458,9 +460,10 @@ static const mips_def_t mips_defs[] = .CP0_PageGrain = (1 << CP0PG_IEC) | (1 << CP0PG_XIE) | (1U << CP0PG_RIE), .CP0_PageGrain_rw_bitmask = 0, - .CP1_fcr0 = (1 << FCR0_FREP) | (1 << FCR0_F64) | (1 << FCR0_L) | - (1 << FCR0_W) | (1 << FCR0_D) | (1 << FCR0_S) | - (0x00 << FCR0_PRID) | (0x0 << FCR0_REV), + .CP1_fcr0 = (1 << FCR0_FREP) | (1 << FCR0_HAS2008) | (1 << FCR0_F64) | + (1 << FCR0_L) | (1 << FCR0_W) | (1 << FCR0_D) | + (1 << FCR0_S) | (0x00 << FCR0_PRID) | (0x0 << FCR0_REV), + .CP1_fcr31 = (1 << FCR31_ABS2008) | (1 << FCR31_NAN2008), .SEGBITS = 32, .PABITS = 32, .insn_flags = CPU_MIPS32R6 | ASE_MICROMIPS, @@ -677,9 +680,10 @@ static const mips_def_t mips_defs[] = .CP0_PageGrain = (1 << CP0PG_IEC) | (1 << CP0PG_XIE) | (1U << CP0PG_RIE), .CP0_PageGrain_rw_bitmask = (1 << CP0PG_ELPA), - .CP1_fcr0 = (1 << FCR0_FREP) | (1 << FCR0_F64) | (1 << FCR0_L) | - (1 << FCR0_W) | (1 << FCR0_D) | (1 << FCR0_S) | - (0x00 << FCR0_PRID) | (0x0 << FCR0_REV), + .CP1_fcr0 = (1 << FCR0_FREP) | (1 << FCR0_HAS2008) | (1 << FCR0_F64) | + (1 << FCR0_L) | (1 << FCR0_W) | (1 << FCR0_D) | + (1 << FCR0_S) | (0x00 << FCR0_PRID) | (0x0 << FCR0_REV), + .CP1_fcr31 = (1 << FCR31_ABS2008) | (1 << FCR31_NAN2008), .SEGBITS = 48, .PABITS = 48, .insn_flags = CPU_MIPS64R6 | ASE_MSA,