From f5718726714cd6114876c4e3ca9b6992ab81176c Mon Sep 17 00:00:00 2001 From: David Gibson Date: Tue, 3 Feb 2015 16:36:21 +1100 Subject: powerpc: Move Power Macintosh drivers to generic byteswappers ppc has special instruction forms to efficiently load and store values in non-native endianness. These can be accessed via the arch-specific {ld,st}_le{16,32}() inlines in arch/powerpc/include/asm/swab.h. However, gcc is perfectly capable of generating the byte-reversing load/store instructions when using the normal, generic cpu_to_le*() and le*_to_cpu() functions eaning the arch-specific functions don't have much point. Worse the "le" in the names of the arch specific functions is now misleading, because they always generate byte-reversing forms, but some ppc machines can now run a little-endian kernel. To start getting rid of the arch-specific forms, this patch removes them from all the old Power Macintosh drivers, replacing them with the generic byteswappers. Signed-off-by: David Gibson Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/include/asm/dbdma.h | 12 ++++++------ arch/powerpc/include/asm/vga.h | 4 ++-- 2 files changed, 8 insertions(+), 8 deletions(-) (limited to 'arch/powerpc/include') diff --git a/arch/powerpc/include/asm/dbdma.h b/arch/powerpc/include/asm/dbdma.h index e23f07e73cb3..6c69836b4ec2 100644 --- a/arch/powerpc/include/asm/dbdma.h +++ b/arch/powerpc/include/asm/dbdma.h @@ -42,12 +42,12 @@ struct dbdma_regs { * DBDMA command structure. These fields are all little-endian! */ struct dbdma_cmd { - unsigned short req_count; /* requested byte transfer count */ - unsigned short command; /* command word (has bit-fields) */ - unsigned int phy_addr; /* physical data address */ - unsigned int cmd_dep; /* command-dependent field */ - unsigned short res_count; /* residual count after completion */ - unsigned short xfer_status; /* transfer status */ + __le16 req_count; /* requested byte transfer count */ + __le16 command; /* command word (has bit-fields) */ + __le32 phy_addr; /* physical data address */ + __le32 cmd_dep; /* command-dependent field */ + __le16 res_count; /* residual count after completion */ + __le16 xfer_status; /* transfer status */ }; /* DBDMA command values in command field */ diff --git a/arch/powerpc/include/asm/vga.h b/arch/powerpc/include/asm/vga.h index e5f8dd366212..ab3acd2f2786 100644 --- a/arch/powerpc/include/asm/vga.h +++ b/arch/powerpc/include/asm/vga.h @@ -25,12 +25,12 @@ static inline void scr_writew(u16 val, volatile u16 *addr) { - st_le16(addr, val); + *addr = cpu_to_le16(val); } static inline u16 scr_readw(volatile const u16 *addr) { - return ld_le16(addr); + return le16_to_cpu(*addr); } #define VT_BUF_HAVE_MEMCPYW -- cgit v1.2.3 From d078eed35de3866cb4af654db87765f53edbacce Mon Sep 17 00:00:00 2001 From: David Gibson Date: Tue, 3 Feb 2015 16:36:24 +1100 Subject: powerpc: Cleanup KVM emulated load/store endian handling Sometimes the KVM code on powerpc needs to emulate load or store instructions from the guest, which can include both normal and byte reversed forms. We currently (AFAICT) handle this correctly, but some variable names are very misleading. In particular we use "is_bigendian" in several places to actually mean "is the IO the same endian as the host", but we now support little-endian powerpc hosts. This also ties into the misleadingly named ld_le*() and st_le*() functions, which in fact always byteswap, even on an LE host. This patch cleans this up by renaming to more accurate "host_swabbed", and uses the generic swab*() functions instead of the powerpc specific and misleadingly named ld_le*() and st_le*() functions. Signed-off-by: David Gibson Reviewed-by: Alexander Graf Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/include/asm/kvm_host.h | 2 +- arch/powerpc/kvm/powerpc.c | 38 ++++++++++++++++++------------------- 2 files changed, 19 insertions(+), 21 deletions(-) (limited to 'arch/powerpc/include') diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h index 8ef05121d3cd..c610961720c7 100644 --- a/arch/powerpc/include/asm/kvm_host.h +++ b/arch/powerpc/include/asm/kvm_host.h @@ -585,7 +585,7 @@ struct kvm_vcpu_arch { pgd_t *pgdir; u8 io_gpr; /* GPR used as IO source/target */ - u8 mmio_is_bigendian; + u8 mmio_host_swabbed; u8 mmio_sign_extend; u8 osi_needed; u8 osi_enabled; diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c index 27c0face86f4..41c5f8f8a20d 100644 --- a/arch/powerpc/kvm/powerpc.c +++ b/arch/powerpc/kvm/powerpc.c @@ -720,7 +720,7 @@ static void kvmppc_complete_mmio_load(struct kvm_vcpu *vcpu, return; } - if (vcpu->arch.mmio_is_bigendian) { + if (!vcpu->arch.mmio_host_swabbed) { switch (run->mmio.len) { case 8: gpr = *(u64 *)run->mmio.data; break; case 4: gpr = *(u32 *)run->mmio.data; break; @@ -728,10 +728,10 @@ static void kvmppc_complete_mmio_load(struct kvm_vcpu *vcpu, case 1: gpr = *(u8 *)run->mmio.data; break; } } else { - /* Convert BE data from userland back to LE. */ switch (run->mmio.len) { - case 4: gpr = ld_le32((u32 *)run->mmio.data); break; - case 2: gpr = ld_le16((u16 *)run->mmio.data); break; + case 8: gpr = swab64(*(u64 *)run->mmio.data); break; + case 4: gpr = swab32(*(u32 *)run->mmio.data); break; + case 2: gpr = swab16(*(u16 *)run->mmio.data); break; case 1: gpr = *(u8 *)run->mmio.data; break; } } @@ -780,14 +780,13 @@ int kvmppc_handle_load(struct kvm_run *run, struct kvm_vcpu *vcpu, int is_default_endian) { int idx, ret; - int is_bigendian; + bool host_swabbed; + /* Pity C doesn't have a logical XOR operator */ if (kvmppc_need_byteswap(vcpu)) { - /* Default endianness is "little endian". */ - is_bigendian = !is_default_endian; + host_swabbed = is_default_endian; } else { - /* Default endianness is "big endian". */ - is_bigendian = is_default_endian; + host_swabbed = !is_default_endian; } if (bytes > sizeof(run->mmio.data)) { @@ -800,7 +799,7 @@ int kvmppc_handle_load(struct kvm_run *run, struct kvm_vcpu *vcpu, run->mmio.is_write = 0; vcpu->arch.io_gpr = rt; - vcpu->arch.mmio_is_bigendian = is_bigendian; + vcpu->arch.mmio_host_swabbed = host_swabbed; vcpu->mmio_needed = 1; vcpu->mmio_is_write = 0; vcpu->arch.mmio_sign_extend = 0; @@ -840,14 +839,13 @@ int kvmppc_handle_store(struct kvm_run *run, struct kvm_vcpu *vcpu, { void *data = run->mmio.data; int idx, ret; - int is_bigendian; + bool host_swabbed; + /* Pity C doesn't have a logical XOR operator */ if (kvmppc_need_byteswap(vcpu)) { - /* Default endianness is "little endian". */ - is_bigendian = !is_default_endian; + host_swabbed = is_default_endian; } else { - /* Default endianness is "big endian". */ - is_bigendian = is_default_endian; + host_swabbed = !is_default_endian; } if (bytes > sizeof(run->mmio.data)) { @@ -862,7 +860,7 @@ int kvmppc_handle_store(struct kvm_run *run, struct kvm_vcpu *vcpu, vcpu->mmio_is_write = 1; /* Store the value at the lowest bytes in 'data'. */ - if (is_bigendian) { + if (!host_swabbed) { switch (bytes) { case 8: *(u64 *)data = val; break; case 4: *(u32 *)data = val; break; @@ -870,11 +868,11 @@ int kvmppc_handle_store(struct kvm_run *run, struct kvm_vcpu *vcpu, case 1: *(u8 *)data = val; break; } } else { - /* Store LE value into 'data'. */ switch (bytes) { - case 4: st_le32(data, val); break; - case 2: st_le16(data, val); break; - case 1: *(u8 *)data = val; break; + case 8: *(u64 *)data = swab64(val); break; + case 4: *(u32 *)data = swab32(val); break; + case 2: *(u16 *)data = swab16(val); break; + case 1: *(u8 *)data = val; break; } } -- cgit v1.2.3 From 0eebf9b5d2da61f84cddd0ec2bb41be93f8fc82b Mon Sep 17 00:00:00 2001 From: David Gibson Date: Tue, 3 Feb 2015 16:36:25 +1100 Subject: powerpc: Remove unused st_le*() and ld_le* functions The powerpc specific st_le*() and ld_le*() functions in arch/powerpc/asm/swab.h no longer have any users. They are also misleadingly named, since they always byteswap, even on a little-endian host. This patch removes them. Signed-off-by: David Gibson Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/include/asm/swab.h | 26 -------------------------- 1 file changed, 26 deletions(-) (limited to 'arch/powerpc/include') diff --git a/arch/powerpc/include/asm/swab.h b/arch/powerpc/include/asm/swab.h index 96f59de61855..487e09077a3e 100644 --- a/arch/powerpc/include/asm/swab.h +++ b/arch/powerpc/include/asm/swab.h @@ -9,30 +9,4 @@ #include -static __inline__ __u16 ld_le16(const volatile __u16 *addr) -{ - __u16 val; - - __asm__ __volatile__ ("lhbrx %0,0,%1" : "=r" (val) : "r" (addr), "m" (*addr)); - return val; -} - -static __inline__ void st_le16(volatile __u16 *addr, const __u16 val) -{ - __asm__ __volatile__ ("sthbrx %1,0,%2" : "=m" (*addr) : "r" (val), "r" (addr)); -} - -static __inline__ __u32 ld_le32(const volatile __u32 *addr) -{ - __u32 val; - - __asm__ __volatile__ ("lwbrx %0,0,%1" : "=r" (val) : "r" (addr), "m" (*addr)); - return val; -} - -static __inline__ void st_le32(volatile __u32 *addr, const __u32 val) -{ - __asm__ __volatile__ ("stwbrx %1,0,%2" : "=m" (*addr) : "r" (val), "r" (addr)); -} - #endif /* _ASM_POWERPC_SWAB_H */ -- cgit v1.2.3