On Mon, Aug 03, 2015 at 04:41:28PM +0200, Andrew Jones wrote: > Add enough RTAS support to support power-off, and apply it to > exit(). > > Signed-off-by: Andrew Jones <[email protected]> > --- > lib/powerpc/asm/rtas.h | 27 ++++++++++++++++ > lib/powerpc/io.c | 3 ++ > lib/powerpc/rtas.c | 84 > +++++++++++++++++++++++++++++++++++++++++++++++++ > lib/ppc64/asm/rtas.h | 1 + > powerpc/Makefile.common | 1 + > powerpc/cstart64.S | 9 ++++++ > 6 files changed, 125 insertions(+) > create mode 100644 lib/powerpc/asm/rtas.h > create mode 100644 lib/powerpc/rtas.c > create mode 100644 lib/ppc64/asm/rtas.h > > diff --git a/lib/powerpc/asm/rtas.h b/lib/powerpc/asm/rtas.h > new file mode 100644 > index 0000000000000..53ce126c69a42 > --- /dev/null > +++ b/lib/powerpc/asm/rtas.h > @@ -0,0 +1,27 @@ > +#ifndef _ASMPOWERPC_RTAS_H_ > +#define _ASMPOWERPC_RTAS_H_ > +/* > + * Copyright (C) 2015, Red Hat Inc, Andrew Jones <[email protected]> > + * > + * This work is licensed under the terms of the GNU LGPL, version 2. > + */ > +#include <libcflat.h> > + > +#define RTAS_UNKNOWN_SERVICE (-1) > + > +struct rtas_args { > + u32 token; > + u32 nargs; > + u32 nret; > + u32 args[16]; > + u32 *rets; > +}; > + > +extern void rtas_init(void); > +extern void enter_rtas(unsigned long args); > +extern int rtas_token(const char *service); > +extern int rtas_call(int token, int nargs, int nret, int *outputs, ...); > + > +extern void rtas_power_off(void); > + > +#endif /* _ASMPOWERPC_RTAS_H_ */ > diff --git a/lib/powerpc/io.c b/lib/powerpc/io.c > index a7eaafeca9205..25cdd0ad961ee 100644 > --- a/lib/powerpc/io.c > +++ b/lib/powerpc/io.c > @@ -7,6 +7,7 @@ > */ > #include <libcflat.h> > #include <asm/spinlock.h> > +#include <asm/rtas.h> > > extern void halt(int code); > extern void putchar(int c); > @@ -15,6 +16,7 @@ static struct spinlock uart_lock; > > void io_init(void) > { > + rtas_init(); > } > > void puts(const char *s) > @@ -27,5 +29,6 @@ void puts(const char *s) > > void exit(int code) > { > + rtas_power_off(); > halt(code); > } > diff --git a/lib/powerpc/rtas.c b/lib/powerpc/rtas.c > new file mode 100644 > index 0000000000000..39f7d4428ee77 > --- /dev/null > +++ b/lib/powerpc/rtas.c > @@ -0,0 +1,84 @@ > +/* > + * powerpc RTAS > + * > + * Copyright (C) 2015, Red Hat Inc, Andrew Jones <[email protected]> > + * > + * This work is licensed under the terms of the GNU LGPL, version 2. > + */ > +#include <libcflat.h> > +#include <libfdt/libfdt.h> > +#include <devicetree.h> > +#include <asm/spinlock.h> > +#include <asm/io.h> > +#include <asm/rtas.h> > + > +static struct spinlock lock; > +struct rtas_args rtas_args; > +static int rtas_node; > + > +void rtas_init(void) > +{ > + if (!dt_available()) { > + printf("%s: No device tree!\n", __func__); > + abort(); > + } > + > + rtas_node = fdt_path_offset(dt_fdt(), "/rtas"); > + if (rtas_node < 0) { > + printf("%s: /rtas node: %s\n", __func__, > + fdt_strerror(rtas_node)); > + abort(); > + } > +} > + > +int rtas_token(const char *service) > +{ > + const struct fdt_property *prop; > + u32 *token; > + > + prop = fdt_get_property(dt_fdt(), rtas_node, service, NULL);
Oh.. one other thing here.
This is only safe if you never alter the device tree blob you're given
(or at least, not after rtas_init()). That may well be the case, but
I don't know your code well enough to be sure.
Otherwise, the rtas node could get moved by other dt changes, meaning
the offset stored in rtas_node is no longer valid.
> + if (prop) {
> + token = (u32 *)prop->data;
> + return fdt32_to_cpu(*token);
> + }
> + return RTAS_UNKNOWN_SERVICE;
> +}
> +
> +int rtas_call(int token, int nargs, int nret, int *outputs, ...)
> +{
> + va_list list;
> + int ret, i;
> +
> + spin_lock(&lock);
> +
> + rtas_args.token = cpu_to_be32(token);
> + rtas_args.nargs = cpu_to_be32(nargs);
> + rtas_args.nret = cpu_to_be32(nret);
> + rtas_args.rets = &rtas_args.args[nargs];
> +
> + va_start(list, outputs);
> + for (i = 0; i < nargs; ++i)
> + rtas_args.args[i] = cpu_to_be32(va_arg(list, u32));
> + va_end(list);
> +
> + for (i = 0; i < nret; ++i)
> + rtas_args.rets[i] = 0;
> +
> + enter_rtas(__pa(&rtas_args));
> +
> + if (nret > 1 && outputs != NULL)
> + for (i = 0; i < nret - 1; ++i)
> + outputs[i] = be32_to_cpu(rtas_args.rets[i + 1]);
> +
> + ret = nret > 0 ? be32_to_cpu(rtas_args.rets[0]) : 0;
> +
> + spin_unlock(&lock);
> + return ret;
> +}
> +
> +void rtas_power_off(void)
> +{
> + printf("RTAS power-off returned %d\n",
> + rtas_call(rtas_token("power-off"), 2, 1, NULL, -1, -1));
> + assert(0);
> +}
> diff --git a/lib/ppc64/asm/rtas.h b/lib/ppc64/asm/rtas.h
> new file mode 100644
> index 0000000000000..fe77f635cd860
> --- /dev/null
> +++ b/lib/ppc64/asm/rtas.h
> @@ -0,0 +1 @@
> +#include "../../powerpc/asm/rtas.h"
> diff --git a/powerpc/Makefile.common b/powerpc/Makefile.common
> index b130342dee60e..f4eff7f8eccb4 100644
> --- a/powerpc/Makefile.common
> +++ b/powerpc/Makefile.common
> @@ -39,6 +39,7 @@ cflatobjs += lib/powerpc/io.o
> cflatobjs += lib/powerpc/setup.o
> cflatobjs += lib/powerpc/mmu.o
> cflatobjs += lib/powerpc/smp.o
> +cflatobjs += lib/powerpc/rtas.o
>
> libgcc := $(shell $(CC) $(machine) --print-libgcc-file-name)
> start_addr := $(shell printf "%x\n" $$(( $(phys_base) + $(kernel_offset) )))
> diff --git a/powerpc/cstart64.S b/powerpc/cstart64.S
> index 8edaaa6e251fc..1c48083efa33c 100644
> --- a/powerpc/cstart64.S
> +++ b/powerpc/cstart64.S
> @@ -8,6 +8,7 @@
>
> #define HVSC .long 0x44000022
> #define H_PUT_TERM_CHAR 0x58
> +#define KVMPPC_H_RTAS 0xf000
>
> #define LOAD_REG_IMMEDIATE(reg,expr) \
> lis reg,(expr)@highest; \
> @@ -85,3 +86,11 @@ putchar:
> li r5, 1 /* sending just 1 byte */
> HVSC
> blr
> +
> +.globl enter_rtas
> +enter_rtas:
> + mr r4, r3
> + lis r3, KVMPPC_H_RTAS@h
> + ori r3, r3, KVMPPC_H_RTAS@l
> + HVSC
> + blr
--
David Gibson | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_
| _way_ _around_!
http://www.ozlabs.org/~dgibson
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