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authorLinus Torvalds <torvalds@linux-foundation.org>2012-07-23 16:22:12 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2012-07-23 16:22:12 -0700
commitfde75430278130505cac21997cd9f90b7bb2670a (patch)
tree909f659117f5fa8bf1b9b46809f4dc655aee0d34 /arch/arm/mach-omap2/omap_hwmod.c
parent1a4120bc101bdc25ec7258937b5071bf34b19cc5 (diff)
parentdb3c47a3af96e8109b1bb114c32f0854259d5970 (diff)
Merge tag 'cleanup2' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull arm-soc cleanups, part 2, from Arnd Bergmann: "These omap cleanups have dependencies on earlier omap branches that in turn depend on other cleanups, so they could not go into the same branch." * tag 'cleanup2' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: ARM: OMAP: sdrc: Fix the build break for OMAP4 only builds ARM: OMAP2+: dmtimer: cleanup fclk usage ARM: OMAP2+: Fix mismerge for omap_hwmod_get_main_clk() API ARM: OMAP2+: Remove unnecessary ifdef around __omap2_set_globals ARM: OMAP2+: am33xx: Change cpu_is_am33xx to soc_is_am33xx ARM: OMAP2+: am33xx: Make am33xx as a separate class ARM: OMAP2+: Move omap3 dpll ops to dpll3xxx.c ARM: OMAP2+: All OMAP2PLUS uses omap-device.o target so add one entry ARM: OMAP: dmtimer: use devm_ API and do some cleanup in probe() ARM: OMAP2+: hwmod code: add support to set dmadisable in hwmod framework ARM: OMAP2+: PRM/CM: Move the stubbed prm and cm functions to prcm.c file and make them __weak ARM: OMAP2+: hwmod: add omap_hwmod_get_main_clk() API ARM: OMAP3+: dpll: optimize noncore dpll locking logic ARM: OMAP3: control: add definition for CONTROL_CAMERA_PHY_CTRL ARM: OMAP2+: powerdomain code: Fix Wake-up power domain power status ARM: OMAP4: clockdomain/CM code: Update supported transition modes ARM: OMAP3/4: omap_hwmod: Add rstst_offs field to struct omap_hwmod_omap4_prcm ARM: OMAP2+: hwmod: Add new sysc_type3 into omap_hwmod required for am33xx
Diffstat (limited to 'arch/arm/mach-omap2/omap_hwmod.c')
-rw-r--r--arch/arm/mach-omap2/omap_hwmod.c76
1 files changed, 71 insertions, 5 deletions
diff --git a/arch/arm/mach-omap2/omap_hwmod.c b/arch/arm/mach-omap2/omap_hwmod.c
index bdc1ec2edb4..5d82bfca38c 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)
@@ -1668,11 +1711,17 @@ 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)
{
@@ -1694,6 +1743,8 @@ 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
@@ -3598,3 +3649,18 @@ void __init omap_hwmod_init(void)
inited = true;
}
+
+/**
+ * omap_hwmod_get_main_clk - get pointer to main clock name
+ * @oh: struct omap_hwmod *
+ *
+ * Returns the main clock name assocated with @oh upon success,
+ * or NULL if @oh is NULL.
+ */
+const char *omap_hwmod_get_main_clk(struct omap_hwmod *oh)
+{
+ if (!oh)
+ return NULL;
+
+ return oh->main_clk;
+}