diff options
author | Tony Lindgren <tony@atomide.com> | 2012-07-05 02:13:04 -0700 |
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committer | Tony Lindgren <tony@atomide.com> | 2012-07-05 02:13:04 -0700 |
commit | ac5b0ea3d00d231dd9cedd45636b29defc368a4c (patch) | |
tree | 9649d193558e7c662257063a77ab7422379ac45b /arch/arm/mach-omap2/omap_hwmod.c | |
parent | 3f96a2d90e6923e2dd1e35d2f149a70a4d0f678c (diff) | |
parent | 8cb8de5d87b75f2ecaa1189079764340ea366c0e (diff) | |
download | blackbird-obmc-linux-ac5b0ea3d00d231dd9cedd45636b29defc368a4c.tar.gz blackbird-obmc-linux-ac5b0ea3d00d231dd9cedd45636b29defc368a4c.zip |
Merge tag 'omap-devel-f-for-3.6' of git://git.kernel.org/pub/scm/linux/kernel/git/pjw/omap-pending into cleanup-part2
Miscellaneous OMAP clock, hwmod, clockdomain, and powerdomain patches
for 3.6. Mostly small infrastructure improvements, and preparation
for OMAP5 and AM33xx code.
Conflicts:
arch/arm/mach-omap2/omap_hwmod.c
arch/arm/plat-omap/include/plat/omap_hwmod.h
Diffstat (limited to 'arch/arm/mach-omap2/omap_hwmod.c')
-rw-r--r-- | arch/arm/mach-omap2/omap_hwmod.c | 61 |
1 files changed, 56 insertions, 5 deletions
diff --git a/arch/arm/mach-omap2/omap_hwmod.c b/arch/arm/mach-omap2/omap_hwmod.c index f97f0624bca0..ebdf0016e536 100644 --- a/arch/arm/mach-omap2/omap_hwmod.c +++ b/arch/arm/mach-omap2/omap_hwmod.c @@ -416,6 +416,49 @@ static int _set_softreset(struct omap_hwmod *oh, u32 *v) } /** + * _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 * * @autoidle: desired AUTOIDLE bitfield value (0 or 1) @@ -1652,11 +1695,17 @@ dis_opt_clks: * 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) { @@ -1678,6 +1727,8 @@ 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 |