From: Alex Elder elder@linaro.org
commit 34a081761e4e3c35381cbfad609ebae2962fe2f8 upstream.
In some cases, the IPA hardware needs to request the always-on subsystem (AOSS) to coordinate with the IPA microcontroller to retain IPA register values at power collapse. This is done by issuing a QMP request to the AOSS microcontroller. A similar request ondoes that request.
We must get and hold the "QMP" handle early, because we might get back EPROBE_DEFER for that. But the actual request should be sent while we know the IPA clock is active, and when we know the microcontroller is operational.
Fixes: 1aac309d3207 ("net: ipa: use autosuspend") Signed-off-by: Alex Elder elder@linaro.org Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/ipa/ipa_power.c | 52 ++++++++++++++++++++++++++++++++++++++++++++ drivers/net/ipa/ipa_power.h | 7 +++++ drivers/net/ipa/ipa_uc.c | 5 ++++ 3 files changed, 64 insertions(+)
--- a/drivers/net/ipa/ipa_power.c +++ b/drivers/net/ipa/ipa_power.c @@ -11,6 +11,8 @@ #include <linux/pm_runtime.h> #include <linux/bitops.h>
+#include "linux/soc/qcom/qcom_aoss.h" + #include "ipa.h" #include "ipa_power.h" #include "ipa_endpoint.h" @@ -64,6 +66,7 @@ enum ipa_power_flag { * struct ipa_power - IPA power management information * @dev: IPA device pointer * @core: IPA core clock + * @qmp: QMP handle for AOSS communication * @spinlock: Protects modem TX queue enable/disable * @flags: Boolean state flags * @interconnect_count: Number of elements in interconnect[] @@ -72,6 +75,7 @@ enum ipa_power_flag { struct ipa_power { struct device *dev; struct clk *core; + struct qmp *qmp; spinlock_t spinlock; /* used with STOPPED/STARTED power flags */ DECLARE_BITMAP(flags, IPA_POWER_FLAG_COUNT); u32 interconnect_count; @@ -382,6 +386,47 @@ void ipa_power_modem_queue_active(struct clear_bit(IPA_POWER_FLAG_STARTED, ipa->power->flags); }
+static int ipa_power_retention_init(struct ipa_power *power) +{ + struct qmp *qmp = qmp_get(power->dev); + + if (IS_ERR(qmp)) { + if (PTR_ERR(qmp) == -EPROBE_DEFER) + return -EPROBE_DEFER; + + /* We assume any other error means it's not defined/needed */ + qmp = NULL; + } + power->qmp = qmp; + + return 0; +} + +static void ipa_power_retention_exit(struct ipa_power *power) +{ + qmp_put(power->qmp); + power->qmp = NULL; +} + +/* Control register retention on power collapse */ +void ipa_power_retention(struct ipa *ipa, bool enable) +{ + static const char fmt[] = "{ class: bcm, res: ipa_pc, val: %c }"; + struct ipa_power *power = ipa->power; + char buf[36]; /* Exactly enough for fmt[]; size a multiple of 4 */ + int ret; + + if (!power->qmp) + return; /* Not needed on this platform */ + + (void)snprintf(buf, sizeof(buf), fmt, enable ? '1' : '0'); + + ret = qmp_send(power->qmp, buf, sizeof(buf)); + if (ret) + dev_err(power->dev, "error %d sending QMP %sable request\n", + ret, enable ? "en" : "dis"); +} + int ipa_power_setup(struct ipa *ipa) { int ret; @@ -438,12 +483,18 @@ ipa_power_init(struct device *dev, const if (ret) goto err_kfree;
+ ret = ipa_power_retention_init(power); + if (ret) + goto err_interconnect_exit; + pm_runtime_set_autosuspend_delay(dev, IPA_AUTOSUSPEND_DELAY); pm_runtime_use_autosuspend(dev); pm_runtime_enable(dev);
return power;
+err_interconnect_exit: + ipa_interconnect_exit(power); err_kfree: kfree(power); err_clk_put: @@ -460,6 +511,7 @@ void ipa_power_exit(struct ipa_power *po
pm_runtime_disable(dev); pm_runtime_dont_use_autosuspend(dev); + ipa_power_retention_exit(power); ipa_interconnect_exit(power); kfree(power); clk_put(clk); --- a/drivers/net/ipa/ipa_power.h +++ b/drivers/net/ipa/ipa_power.h @@ -41,6 +41,13 @@ void ipa_power_modem_queue_wake(struct i void ipa_power_modem_queue_active(struct ipa *ipa);
/** + * ipa_power_retention() - Control register retention on power collapse + * @ipa: IPA pointer + * @enable: Whether retention should be enabled or disabled + */ +void ipa_power_retention(struct ipa *ipa, bool enable); + +/** * ipa_power_setup() - Set up IPA power management * @ipa: IPA pointer * --- a/drivers/net/ipa/ipa_uc.c +++ b/drivers/net/ipa/ipa_uc.c @@ -11,6 +11,7 @@
#include "ipa.h" #include "ipa_uc.h" +#include "ipa_power.h"
/** * DOC: The IPA embedded microcontroller @@ -154,6 +155,7 @@ static void ipa_uc_response_hdlr(struct case IPA_UC_RESPONSE_INIT_COMPLETED: if (ipa->uc_powered) { ipa->uc_loaded = true; + ipa_power_retention(ipa, true); pm_runtime_mark_last_busy(dev); (void)pm_runtime_put_autosuspend(dev); ipa->uc_powered = false; @@ -184,6 +186,9 @@ void ipa_uc_deconfig(struct ipa *ipa)
ipa_interrupt_remove(ipa->interrupt, IPA_IRQ_UC_1); ipa_interrupt_remove(ipa->interrupt, IPA_IRQ_UC_0); + if (ipa->uc_loaded) + ipa_power_retention(ipa, false); + if (!ipa->uc_powered) return;