Re: [PATCH V6 16/21] soc/tegra: pmc: Add pmc wake support for tegra210
From: Sowjanya Komatineni
Date: Mon Jul 22 2019 - 23:09:54 EST
On 7/22/19 8:03 PM, Dmitry Osipenko wrote:
23.07.2019 4:52, Sowjanya Komatineni ÐÐÑÐÑ:
On 7/22/19 6:41 PM, Dmitry Osipenko wrote:
23.07.2019 4:08, Dmitry Osipenko ÐÐÑÐÑ:
23.07.2019 3:58, Dmitry Osipenko ÐÐÑÐÑ:
21.07.2019 22:40, Sowjanya Komatineni ÐÐÑÐÑ:
This patch implements PMC wakeup sequence for Tegra210 and defines
common used RTC alarm wake event.
Signed-off-by: Sowjanya Komatineni <skomatineni@xxxxxxxxxx>
---
drivers/soc/tegra/pmc.c | 111 ++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 111 insertions(+)
diff --git a/drivers/soc/tegra/pmc.c b/drivers/soc/tegra/pmc.c
index 91c84d0e66ae..c556f38874e1 100644
--- a/drivers/soc/tegra/pmc.c
+++ b/drivers/soc/tegra/pmc.c
@@ -57,6 +57,12 @@
#define PMC_CNTRL_SYSCLK_OE BIT(11) /* system clock enable */
#define PMC_CNTRL_SYSCLK_POLARITY BIT(10) /* sys clk polarity */
#define PMC_CNTRL_MAIN_RST BIT(4)
+#define PMC_CNTRL_LATCH_WAKEUPS BIT(5)
Please follow the TRM's bits naming.
PMC_CNTRL_LATCHWAKE_EN
+#define PMC_WAKE_MASK 0x0c
+#define PMC_WAKE_LEVEL 0x10
+#define PMC_WAKE_STATUS 0x14
+#define PMC_SW_WAKE_STATUS 0x18
#define DPD_SAMPLE 0x020
#define DPD_SAMPLE_ENABLE BIT(0)
@@ -87,6 +93,11 @@
#define PMC_SCRATCH41 0x140
+#define PMC_WAKE2_MASK 0x160
+#define PMC_WAKE2_LEVEL 0x164
+#define PMC_WAKE2_STATUS 0x168
+#define PMC_SW_WAKE2_STATUS 0x16c
+
#define PMC_SENSOR_CTRL 0x1b0
#define PMC_SENSOR_CTRL_SCRATCH_WRITE BIT(2)
#define PMC_SENSOR_CTRL_ENABLE_RST BIT(1)
@@ -1922,6 +1933,55 @@ static const struct irq_domain_ops tegra_pmc_irq_domain_ops = {
.alloc = tegra_pmc_irq_alloc,
};
+static int tegra210_pmc_irq_set_wake(struct irq_data *data, unsigned int on)
+{
+ struct tegra_pmc *pmc = irq_data_get_irq_chip_data(data);
+ unsigned int offset, bit;
+ u32 value;
+
+ if (data->hwirq == ULONG_MAX)
+ return 0;
+
+ offset = data->hwirq / 32;
+ bit = data->hwirq % 32;
+
+ /*
+ * Latch wakeups to SW_WAKE_STATUS register to capture events
+ * that would not make it into wakeup event register during LP0 exit.
+ */
+ value = tegra_pmc_readl(pmc, PMC_CNTRL);
+ value |= PMC_CNTRL_LATCH_WAKEUPS;
+ tegra_pmc_writel(pmc, value, PMC_CNTRL);
+ udelay(120);
Why it takes so much time to latch the values? Shouldn't some status-bit
be polled for the completion of latching?
Is this register-write really getting buffered in the PMC?
+ value &= ~PMC_CNTRL_LATCH_WAKEUPS;
+ tegra_pmc_writel(pmc, value, PMC_CNTRL);
+ udelay(120);
120 usecs to remove latching, really?
+ tegra_pmc_writel(pmc, 0, PMC_SW_WAKE_STATUS);
+ tegra_pmc_writel(pmc, 0, PMC_SW_WAKE2_STATUS);
+
+ tegra_pmc_writel(pmc, 0, PMC_WAKE_STATUS);
+ tegra_pmc_writel(pmc, 0, PMC_WAKE2_STATUS);
+
+ /* enable PMC wake */
+ if (data->hwirq >= 32)
+ offset = PMC_WAKE2_MASK;
+ else
+ offset = PMC_WAKE_MASK;
+
+ value = tegra_pmc_readl(pmc, offset);
+
+ if (on)
+ value |= 1 << bit;
+ else
+ value &= ~(1 << bit);
+
+ tegra_pmc_writel(pmc, value, offset);
Why the latching is done *before* writing into the WAKE registers? What
it is latching then?
I'm looking at the TRM doc and it says that latching should be done
*after* writing to the WAKE_MASK / LEVEL registers.
Secondly it says that it's enough to do:
value = tegra_pmc_readl(pmc, PMC_CNTRL);
value |= PMC_CNTRL_LATCH_WAKEUPS;
tegra_pmc_writel(pmc, value, PMC_CNTRL);
in order to latch. There is no need for the delay and to remove the
"LATCHWAKE_EN" bit, it should be a oneshot action.
Although, no. TRM says "stops latching on transition from 1
to 0 (sequence - set to 1,set to 0)", so it's not a oneshot action.
Have you tested this code at all? I'm wondering how it happens to work
without a proper latching.
Yes, ofcourse its tested and this sequence to do transition is
recommendation from Tegra designer.
Will check if TRM doesn't have update properly or will re-confirm
internally on delay time...
On any of the wake event PMC wakeup happens and WAKE_STATUS register
will have bits set for all events that triggered wake.
After wakeup PMC doesn't update SW_WAKE_STATUS register as per PMC design.
SW latch register added in design helps to provide a way to capture
those events that happen right during wakeup time and didnt make it to
SW_WAKE_STATUS register.
So before next suspend entry, latching all prior wake events into SW
WAKE_STATUS and then clearing them.
I'm now wondering whether the latching cold be turned ON permanently
during of the PMC's probe, for simplicity.
latching should be done on suspend-resume cycle as wake events gets
generates on every suspend-resume cycle.
LATCHWAKE_EN - When set, enables latching and stops latching on
transition from 1 to 0
There is recommendation of min 120uSec for this transition to stop
latching. Will double-check why 120uSec
Yes, please check.
+ return 0;
+}
+
static int tegra186_pmc_irq_set_wake(struct irq_data *data, unsigned int on)
{
struct tegra_pmc *pmc = irq_data_get_irq_chip_data(data);
@@ -1954,6 +2014,49 @@ static int tegra186_pmc_irq_set_wake(struct irq_data *data, unsigned int on)
return 0;
}
+static int tegra210_pmc_irq_set_type(struct irq_data *data, unsigned int type)
+{
+ struct tegra_pmc *pmc = irq_data_get_irq_chip_data(data);
+ unsigned int offset, bit;
+ u32 value;
+
+ if (data->hwirq == ULONG_MAX)
+ return 0;
+
+ offset = data->hwirq / 32;
+ bit = data->hwirq % 32;
+
+ if (data->hwirq >= 32)
+ offset = PMC_WAKE2_LEVEL;
+ else
+ offset = PMC_WAKE_LEVEL;
+
+ value = tegra_pmc_readl(pmc, offset);
+
+ switch (type) {
+ case IRQ_TYPE_EDGE_RISING:
+ case IRQ_TYPE_LEVEL_HIGH:
+ value |= 1 << bit;
+ break;
+
+ case IRQ_TYPE_EDGE_FALLING:
+ case IRQ_TYPE_LEVEL_LOW:
+ value &= ~(1 << bit);
+ break;
+
+ case IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING:
+ value ^= 1 << bit;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ tegra_pmc_writel(pmc, value, offset);
Shouldn't the WAKE_LEVEL be latched as well?
WAKE_LEVELs dont need any latch as they are the levels SW sets for wake
trigger and they are not status
Okay.
[snip]