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author | Nicolas Boichat <drinkcat@chromium.org> | 2019-06-26 06:54:45 +0300 |
---|---|---|
committer | Linus Walleij <linus.walleij@linaro.org> | 2019-06-27 14:22:11 +0300 |
commit | 9d957a959bc8c3dfe37572ac8e99affb5a885965 (patch) | |
tree | 77e99fc0c0e3d7a3d9ed7b73a97f2dcd49d0938f | |
parent | 35594bc7cecf3a78504b590e350570e8f4d7779e (diff) | |
download | linux-9d957a959bc8c3dfe37572ac8e99affb5a885965.tar.xz |
pinctrl: mediatek: Update cur_mask in mask/mask ops
During suspend/resume, mtk_eint_mask may be called while
wake_mask is active. For example, this happens if a wake-source
with an active interrupt handler wakes the system:
irq/pm.c:irq_pm_check_wakeup would disable the interrupt, so
that it can be handled later on in the resume flow.
However, this may happen before mtk_eint_do_resume is called:
in this case, wake_mask is loaded, and cur_mask is restored
from an older copy, re-enabling the interrupt, and causing
an interrupt storm (especially for level interrupts).
Step by step, for a line that has both wake and interrupt enabled:
1. cur_mask[irq] = 1; wake_mask[irq] = 1; EINT_EN[irq] = 1 (interrupt
enabled at hardware level)
2. System suspends, resumes due to that line (at this stage EINT_EN
== wake_mask)
3. irq_pm_check_wakeup is called, and disables the interrupt =>
EINT_EN[irq] = 0, but we still have cur_mask[irq] = 1
4. mtk_eint_do_resume is called, and restores EINT_EN = cur_mask, so
it reenables EINT_EN[irq] = 1 => interrupt storm as the driver
is not yet ready to handle the interrupt.
This patch fixes the issue in step 3, by recording all mask/unmask
changes in cur_mask. This also avoids the need to read the current
mask in eint_do_suspend, and we can remove mtk_eint_chip_read_mask
function.
The interrupt will be re-enabled properly later on, sometimes after
mtk_eint_do_resume, when the driver is ready to handle it.
Fixes: 58a5e1b64bb0 ("pinctrl: mediatek: Implement wake handler and suspend resume")
Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>
Acked-by: Sean Wang <sean.wang@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
-rw-r--r-- | drivers/pinctrl/mediatek/mtk-eint.c | 18 |
1 files changed, 4 insertions, 14 deletions
diff --git a/drivers/pinctrl/mediatek/mtk-eint.c b/drivers/pinctrl/mediatek/mtk-eint.c index 737385e86beb..7e526bcf5e0b 100644 --- a/drivers/pinctrl/mediatek/mtk-eint.c +++ b/drivers/pinctrl/mediatek/mtk-eint.c @@ -113,6 +113,8 @@ static void mtk_eint_mask(struct irq_data *d) void __iomem *reg = mtk_eint_get_offset(eint, d->hwirq, eint->regs->mask_set); + eint->cur_mask[d->hwirq >> 5] &= ~mask; + writel(mask, reg); } @@ -123,6 +125,8 @@ static void mtk_eint_unmask(struct irq_data *d) void __iomem *reg = mtk_eint_get_offset(eint, d->hwirq, eint->regs->mask_clr); + eint->cur_mask[d->hwirq >> 5] |= mask; + writel(mask, reg); if (eint->dual_edge[d->hwirq]) @@ -217,19 +221,6 @@ static void mtk_eint_chip_write_mask(const struct mtk_eint *eint, } } -static void mtk_eint_chip_read_mask(const struct mtk_eint *eint, - void __iomem *base, u32 *buf) -{ - int port; - void __iomem *reg; - - for (port = 0; port < eint->hw->ports; port++) { - reg = base + eint->regs->mask + (port << 2); - buf[port] = ~readl_relaxed(reg); - /* Mask is 0 when irq is enabled, and 1 when disabled. */ - } -} - static int mtk_eint_irq_request_resources(struct irq_data *d) { struct mtk_eint *eint = irq_data_get_irq_chip_data(d); @@ -384,7 +375,6 @@ static void mtk_eint_irq_handler(struct irq_desc *desc) int mtk_eint_do_suspend(struct mtk_eint *eint) { - mtk_eint_chip_read_mask(eint, eint->base, eint->cur_mask); mtk_eint_chip_write_mask(eint, eint->base, eint->wake_mask); return 0; |