diff --git a/arch/arm/mach-omap2/omap_hwmod.c b/arch/arm/mach-omap2/omap_hwmod.c index a89214ee4694772c99de98db56321472c24fe656..98cde62c0cacec1e7cdc6f33e4d6eabb3e3ba57f 100644 --- a/arch/arm/mach-omap2/omap_hwmod.c +++ b/arch/arm/mach-omap2/omap_hwmod.c @@ -387,6 +387,49 @@ static int _set_softreset(struct omap_hwmod *oh, u32 *v) return 0; } +/** + * _set_dmadisable: set OCP_SYSCONFIG.DMADISABLE bit in @v + * @oh: struct omap_hwmod * + * + * The DMADISABLE bit is a semi-automatic bit present in sysconfig register + * of some modules. When the DMA must perform read/write accesses, the + * DMADISABLE bit is cleared by the hardware. But when the DMA must stop + * for power management, software must set the DMADISABLE bit back to 1. + * + * Set the DMADISABLE bit in @v for hwmod @oh. Returns -EINVAL upon + * error or 0 upon success. + */ +static int _set_dmadisable(struct omap_hwmod *oh) +{ + u32 v; + u32 dmadisable_mask; + + if (!oh->class->sysc || + !(oh->class->sysc->sysc_flags & SYSC_HAS_DMADISABLE)) + return -EINVAL; + + if (!oh->class->sysc->sysc_fields) { + WARN(1, "omap_hwmod: %s: offset struct for sysconfig not provided in class\n", oh->name); + return -EINVAL; + } + + /* clocks must be on for this operation */ + if (oh->_state != _HWMOD_STATE_ENABLED) { + pr_warn("omap_hwmod: %s: dma can be disabled only from enabled state\n", oh->name); + return -EINVAL; + } + + pr_debug("omap_hwmod: %s: setting DMADISABLE\n", oh->name); + + v = oh->_sysc_cache; + dmadisable_mask = + (0x1 << oh->class->sysc->sysc_fields->dmadisable_shift); + v |= dmadisable_mask; + _write_sysconfig(v, oh); + + return 0; +} + /** * _set_module_autoidle: set the OCP_SYSCONFIG AUTOIDLE field in @v * @oh: struct omap_hwmod * @@ -1698,11 +1741,17 @@ static int _ocp_softreset(struct omap_hwmod *oh) * therefore have no OCP header registers to access. Others (like the * IVA) have idiosyncratic reset sequences. So for these relatively * rare cases, custom reset code can be supplied in the struct - * omap_hwmod_class .reset function pointer. Passes along the return - * value from either _ocp_softreset() or the custom reset function - - * these must return -EINVAL if the hwmod cannot be reset this way or - * if the hwmod is in the wrong state, -ETIMEDOUT if the module did - * not reset in time, or 0 upon success. + * omap_hwmod_class .reset function pointer. + * + * _set_dmadisable() is called to set the DMADISABLE bit so that it + * does not prevent idling of the system. This is necessary for cases + * where ROMCODE/BOOTLOADER uses dma and transfers control to the + * kernel without disabling dma. + * + * Passes along the return value from either _ocp_softreset() or the + * custom reset function - these must return -EINVAL if the hwmod + * cannot be reset this way or if the hwmod is in the wrong state, + * -ETIMEDOUT if the module did not reset in time, or 0 upon success. */ static int _reset(struct omap_hwmod *oh) { @@ -1724,6 +1773,8 @@ static int _reset(struct omap_hwmod *oh) } } + _set_dmadisable(oh); + /* * OCP_SYSCONFIG bits need to be reprogrammed after a * softreset. The _enable() function should be split to avoid diff --git a/arch/arm/mach-omap2/omap_hwmod_common_data.c b/arch/arm/mach-omap2/omap_hwmod_common_data.c index 51e5418899fb446cd2317efe2622e3683860eec4..aff613852911aba50f3cab37a5eb3fd4ae945701 100644 --- a/arch/arm/mach-omap2/omap_hwmod_common_data.c +++ b/arch/arm/mach-omap2/omap_hwmod_common_data.c @@ -47,6 +47,7 @@ struct omap_hwmod_sysc_fields omap_hwmod_sysc_type2 = { .midle_shift = SYSC_TYPE2_MIDLEMODE_SHIFT, .sidle_shift = SYSC_TYPE2_SIDLEMODE_SHIFT, .srst_shift = SYSC_TYPE2_SOFTRESET_SHIFT, + .dmadisable_shift = SYSC_TYPE2_DMADISABLE_SHIFT, }; struct omap_dss_dispc_dev_attr omap2_3_dss_dispc_dev_attr = { diff --git a/arch/arm/plat-omap/include/plat/omap_hwmod.h b/arch/arm/plat-omap/include/plat/omap_hwmod.h index da22acd0ce7aefb5729b1347fd75f50d825a9878..27455ed0a2abc976a10e1d0321853145bb8bd4dc 100644 --- a/arch/arm/plat-omap/include/plat/omap_hwmod.h +++ b/arch/arm/plat-omap/include/plat/omap_hwmod.h @@ -69,6 +69,8 @@ extern struct omap_hwmod_sysc_fields omap_hwmod_sysc_type2; #define SYSC_TYPE2_SIDLEMODE_MASK (0x3 << SYSC_TYPE2_SIDLEMODE_SHIFT) #define SYSC_TYPE2_MIDLEMODE_SHIFT 4 #define SYSC_TYPE2_MIDLEMODE_MASK (0x3 << SYSC_TYPE2_MIDLEMODE_SHIFT) +#define SYSC_TYPE2_DMADISABLE_SHIFT 16 +#define SYSC_TYPE2_DMADISABLE_MASK (0x1 << SYSC_TYPE2_DMADISABLE_SHIFT) /* OCP SYSSTATUS bit shifts/masks */ #define SYSS_RESETDONE_SHIFT 0 @@ -283,6 +285,7 @@ struct omap_hwmod_ocp_if { #define SYSS_HAS_RESET_STATUS (1 << 7) #define SYSC_NO_CACHE (1 << 8) /* XXX SW flag, belongs elsewhere */ #define SYSC_HAS_RESET_STATUS (1 << 9) +#define SYSC_HAS_DMADISABLE (1 << 10) /* omap_hwmod_sysconfig.clockact flags */ #define CLOCKACT_TEST_BOTH 0x0 @@ -298,6 +301,7 @@ struct omap_hwmod_ocp_if { * @enwkup_shift: Offset of the enawakeup bit * @srst_shift: Offset of the softreset bit * @autoidle_shift: Offset of the autoidle bit + * @dmadisable_shift: Offset of the dmadisable bit */ struct omap_hwmod_sysc_fields { u8 midle_shift; @@ -306,6 +310,7 @@ struct omap_hwmod_sysc_fields { u8 enwkup_shift; u8 srst_shift; u8 autoidle_shift; + u8 dmadisable_shift; }; /**