diff options
Diffstat (limited to 'arch/powerpc/kernel/epapr_paravirt.c')
-rw-r--r-- | arch/powerpc/kernel/epapr_paravirt.c | 85 |
1 files changed, 85 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/epapr_paravirt.c b/arch/powerpc/kernel/epapr_paravirt.c new file mode 100644 index 000000000..59e4ba749 --- /dev/null +++ b/arch/powerpc/kernel/epapr_paravirt.c @@ -0,0 +1,85 @@ +/* + * ePAPR para-virtualization support. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License, version 2, as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + * + * Copyright (C) 2012 Freescale Semiconductor, Inc. + */ + +#include <linux/of.h> +#include <linux/of_fdt.h> +#include <asm/epapr_hcalls.h> +#include <asm/cacheflush.h> +#include <asm/code-patching.h> +#include <asm/machdep.h> + +#if !defined(CONFIG_64BIT) || defined(CONFIG_PPC_BOOK3E_64) +extern void epapr_ev_idle(void); +extern u32 epapr_ev_idle_start[]; +#endif + +bool epapr_paravirt_enabled; +static bool __maybe_unused epapr_has_idle; + +static int __init early_init_dt_scan_epapr(unsigned long node, + const char *uname, + int depth, void *data) +{ + const u32 *insts; + int len; + int i; + + insts = of_get_flat_dt_prop(node, "hcall-instructions", &len); + if (!insts) + return 0; + + if (len % 4 || len > (4 * 4)) + return -1; + + for (i = 0; i < (len / 4); i++) { + u32 inst = be32_to_cpu(insts[i]); + patch_instruction(epapr_hypercall_start + i, inst); +#if !defined(CONFIG_64BIT) || defined(CONFIG_PPC_BOOK3E_64) + patch_instruction(epapr_ev_idle_start + i, inst); +#endif + } + +#if !defined(CONFIG_64BIT) || defined(CONFIG_PPC_BOOK3E_64) + if (of_get_flat_dt_prop(node, "has-idle", NULL)) + epapr_has_idle = true; +#endif + + epapr_paravirt_enabled = true; + + return 1; +} + +int __init epapr_paravirt_early_init(void) +{ + of_scan_flat_dt(early_init_dt_scan_epapr, NULL); + + return 0; +} + +static int __init epapr_idle_init(void) +{ +#if !defined(CONFIG_64BIT) || defined(CONFIG_PPC_BOOK3E_64) + if (epapr_has_idle) + ppc_md.power_save = epapr_ev_idle; +#endif + + return 0; +} + +postcore_initcall(epapr_idle_init); |