static void omap2_iommu_disable(struct omap_iommu *obj)
{
struct omap_hwmod *oh;
u32 l;
oh = omap_hwmod_lookup(obj->name);
if (!oh)
return;
/*
* IPU and DSP iommus are not directly connected to the processor
* instead they are behind a shared MMU. Therefore in the case of
* a mmu fault and the mmu fault was not handled, even if the processor
* is under reset, the shared MMU will try to translation the address
* again causing that the status flag cannot be clear and therefore
* as soon as the clkdm wants to go to idle the clkdm will be stuck
* in transition state. The only way to reset the shared MMU is doing
* a hardreset of the L2 iommu which shared the reset line with the
* shared MMU. That way we can clean the status bit and turn off
* the iommu without any issue.
*/
if (!strcmp(obj->name, "ipu") || !strcmp(obj->name, "dsp")) {
omap_hwmod_assert_hardreset(oh, oh->rst_lines->name);
omap_hwmod_deassert_hardreset(oh, oh->rst_lines->name);
goto out;
}
l = iommu_read_reg(obj, MMU_IRQSTATUS);
iommu_write_reg(obj, l, MMU_IRQSTATUS);
l = iommu_read_reg(obj, MMU_CNTL);
l &= ~MMU_CNTL_MASK;
iommu_write_reg(obj, l, MMU_CNTL);
out:
clkdm_allow_idle(oh->clkdm);
dev_dbg(obj->dev, "%s is shutting down\n", obj->name);
}
/**
* omap_device_assert_hardreset - set a device's hardreset line
* @pdev: struct platform_device * to reset
* @name: const char * name of the reset line
*
* Set the hardreset line identified by @name on the IP blocks
* associated with the hwmods backing the platform_device @pdev. All
* of the hwmods associated with @pdev must have the same hardreset
* line linked to them for this to work. Passes along the return value
* of omap_hwmod_assert_hardreset() in the event of any failure, or
* returns 0 upon success.
*/
int omap_device_assert_hardreset(struct platform_device *pdev, const char *name)
{
struct omap_device *od = to_omap_device(pdev);
int ret = 0;
int i;
for (i = 0; i < od->hwmods_cnt; i++) {
ret = omap_hwmod_assert_hardreset(od->hwmods[i], name);
if (ret)
break;
}
return ret;
}