On 09/24/2014 11:41 PM, Cyril Bur wrote: > Added simple accessor functions for rtas in memory buffers which performs > accesses of appropriate type and performs endian conversions. > > Signed-off-by: Cyril Bur <cyril....@au1.ibm.com> > --- > arch/powerpc/platforms/pseries/Makefile | 4 +- > arch/powerpc/platforms/pseries/pseries.h | 41 +++++++++ > arch/powerpc/platforms/pseries/rtas_buffer.c | 126 > +++++++++++++++++++++++++++ > 3 files changed, 170 insertions(+), 1 deletion(-) > create mode 100644 arch/powerpc/platforms/pseries/rtas_buffer.c
Maybe Michael has an opinion here, but seems to me since this is all RTAS related it would make sense for this code to belong in kernel/rtas.c and include/asm/rtas.h. -Tyrel > > diff --git a/arch/powerpc/platforms/pseries/Makefile > b/arch/powerpc/platforms/pseries/Makefile > index 0348079..7eb7c46 100644 > --- a/arch/powerpc/platforms/pseries/Makefile > +++ b/arch/powerpc/platforms/pseries/Makefile > @@ -3,7 +3,9 @@ ccflags-$(CONFIG_PPC_PSERIES_DEBUG) += -DDEBUG > > obj-y := lpar.o hvCall.o nvram.o reconfig.o \ > setup.o iommu.o event_sources.o ras.o \ > - firmware.o power.o dlpar.o mobility.o rng.o > + firmware.o power.o dlpar.o mobility.o \ > + rng.o rtas_buffer.o > + > obj-$(CONFIG_SMP) += smp.o > obj-$(CONFIG_SCANLOG) += scanlog.o > obj-$(CONFIG_EEH) += eeh_pseries.o > diff --git a/arch/powerpc/platforms/pseries/pseries.h > b/arch/powerpc/platforms/pseries/pseries.h > index 361add6..f24e352 100644 > --- a/arch/powerpc/platforms/pseries/pseries.h > +++ b/arch/powerpc/platforms/pseries/pseries.h > @@ -66,4 +66,45 @@ int pseries_root_bridge_prepare(struct pci_host_bridge > *bridge); > > unsigned long pseries_memory_block_size(void); > > +/* Manipulation of the in memory data returned from an RTAS call */ > + > +/* Data pointed to by ptr is in big endian */ > +struct rtas_buffer { > + void *ptr; > + int len; > + int pos; > +}; > + > +/* Buffer is already zeroed */ > +int make_rtas_buf(struct rtas_buffer *b, size_t size); > +void free_rtas_buf(struct rtas_buffer *b); > + > +/* Return pointer to the buffer being used */ > +void *get_rtas_buf(struct rtas_buffer *b); > + > +/* Checks if the buffer exists and the read position is less than the > length*/ > +bool check_rtas_buf(struct rtas_buffer *b); > +size_t get_rtas_buf_size(struct rtas_buffer *b); > + > +/* Advance the internal position of the buffer by size bytes */ > +bool advance_rtas_buf(struct rtas_buffer *b, size_t size); > + > +/* Put a value val into the buffer at position pos. Function expect val in > cpu > + * endian. Returns true if the write to the buffer was successful. > + */ > +bool put_rtas_buf_32(struct rtas_buffer *b, u32 val, int pos); > + > +/* Grab the byte at the current position of the buffer without incrementing > + * the internal position of the buffer */ > +bool peek_rtas_buf(struct rtas_buffer *b, u8 *c); > + > +/* Accessor functions return true if access succeeded and value is written to > + * val in cpu endian. Automatically advances its reference into the buffer by > + * the requested amount. > + */ > +bool get_rtas_buf_32(struct rtas_buffer *b, u32 *val); > +bool get_rtas_buf_64(struct rtas_buffer *b, u64 *val); > +bool get_rtas_buf_mem(struct rtas_buffer *b, void **p, size_t len); > +bool get_rtas_buf_str(struct rtas_buffer *b, char **s); > + > #endif /* _PSERIES_PSERIES_H */ > diff --git a/arch/powerpc/platforms/pseries/rtas_buffer.c > b/arch/powerpc/platforms/pseries/rtas_buffer.c > new file mode 100644 > index 0000000..f06b73c > --- /dev/null > +++ b/arch/powerpc/platforms/pseries/rtas_buffer.c > @@ -0,0 +1,126 @@ > +#include <linux/kernel.h> > +#include <linux/slab.h> > + > +#include "pseries.h" > + > + > +int make_rtas_buf(struct rtas_buffer *b, size_t sz) > +{ > + b->ptr = kzalloc(sz, GFP_KERNEL); > + b->len = sz; > + b->pos = 0; > + return (!b->ptr) ? -ENOMEM : 0; > +} > + > +void free_rtas_buf(struct rtas_buffer *b) > +{ > + kfree(b->ptr); > +} > + > +void *get_rtas_buf(struct rtas_buffer *b) > +{ > + return (b) ? b->ptr : NULL; > +} > + > +size_t get_rtas_buf_size(struct rtas_buffer *b) > +{ > + return (b) ? b->len : 0; > +} > + > +bool check_rtas_buf(struct rtas_buffer *b) > +{ > + return (b && b->ptr && b->pos < b->len); > +} > + > +static inline void *buf_pos(struct rtas_buffer *b) > +{ > + return (b && b->ptr) ? b->ptr + b->pos : NULL; > +} > + > +bool peek_rtas_buf(struct rtas_buffer *b, u8 *c) > +{ > + if (!b || !c || b->pos >= b->len) > + return false; > + > + *c = *(u8 *)buf_pos(b); > + > + return true; > +} > + > +bool put_rtas_buf_32(struct rtas_buffer *b, u32 val, int pos) > +{ > + if (!b || b->pos >= b->len) > + return false; > + > + *((__be32 *)buf_pos(b)) = cpu_to_be32(val); > + > + return true; > +} > + > +bool get_rtas_buf_32(struct rtas_buffer *b, u32 *val) > +{ > + if (!b || !val || b->len - b->pos < sizeof(u32)) > + return false; > + > + *val = be32_to_cpu(*((__be32 *)buf_pos(b))); > + b->pos += sizeof(u32); > + return true; > +} > + > +bool get_rtas_buf_64(struct rtas_buffer *b, u64 *val) > +{ > + if (!b || !val || b->len - b->pos < sizeof(u64)) > + return false; > + > + *val = be64_to_cpu(*((__be64 *)buf_pos(b))); > + b->pos += sizeof(u64); > + return true; > +} > + > +bool get_rtas_buf_str(struct rtas_buffer *b, char **s) > +{ > + int i; > + if (!b || !s) > + return false; > + > + /* Get length of string */ > + i = b->pos; > + while (i < b->len) { > + if (*(char *)(b->ptr + i) == '\0') { > + *s = (char *)buf_pos(b); > + if (!*s) > + return false; > + > + b->pos = i + 1; > + return true; > + } > + i++; > + } > + > + return false; > +} > + > +bool get_rtas_buf_mem(struct rtas_buffer *b, void **p, size_t len) > +{ > + if (!b || !p || b->len - b->pos < len) > + return false; > + > + *p = buf_pos(b); > + if (!*p) > + return false; > + > + b->pos += len; > + > + return true; > +} > + > +bool advance_rtas_buf(struct rtas_buffer *b, size_t len) > +{ > + if (!b || b->len - b->pos < len) > + return false; > + > + b->pos += len; > + > + return true; > +} > + > _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev