diff options
Diffstat (limited to 'arch/arm/mach-omap2/cm.c')
-rw-r--r-- | arch/arm/mach-omap2/cm.c | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/cm.c b/arch/arm/mach-omap2/cm.c new file mode 100644 index 000000000000..8eb2dab8c7db --- /dev/null +++ b/arch/arm/mach-omap2/cm.c @@ -0,0 +1,70 @@ +/* + * OMAP2/3 CM module functions + * + * Copyright (C) 2009 Nokia Corporation + * Paul Walmsley + * + * 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. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/types.h> +#include <linux/delay.h> +#include <linux/spinlock.h> +#include <linux/list.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/io.h> + +#include <asm/atomic.h> + +#include "cm.h" +#include "cm-regbits-24xx.h" +#include "cm-regbits-34xx.h" + +/* MAX_MODULE_READY_TIME: max milliseconds for module to leave idle */ +#define MAX_MODULE_READY_TIME 20000 + +static const u8 cm_idlest_offs[] = { + CM_IDLEST1, CM_IDLEST2, OMAP2430_CM_IDLEST3 +}; + +/** + * omap2_cm_wait_idlest_ready - wait for a module to leave idle or standby + * @prcm_mod: PRCM module offset + * @idlest_id: CM_IDLESTx register ID (i.e., x = 1, 2, 3) + * @idlest_shift: shift of the bit in the CM_IDLEST* register to check + * + * XXX document + */ +int omap2_cm_wait_module_ready(s16 prcm_mod, u8 idlest_id, u8 idlest_shift) +{ + int ena = 0, i = 0; + u8 cm_idlest_reg; + u32 mask; + + if (!idlest_id || (idlest_id > ARRAY_SIZE(cm_idlest_offs))) + return -EINVAL; + + cm_idlest_reg = cm_idlest_offs[idlest_id - 1]; + + if (cpu_is_omap24xx()) + ena = idlest_shift; + else if (cpu_is_omap34xx()) + ena = 0; + else + BUG(); + + mask = 1 << idlest_shift; + + /* XXX should be OMAP2 CM */ + while (((cm_read_mod_reg(prcm_mod, cm_idlest_reg) & mask) != ena) && + (i++ < MAX_MODULE_READY_TIME)) + udelay(1); + + return (i < MAX_MODULE_READY_TIME) ? 0 : -EBUSY; +} + |