wil6210: prevent deep sleep of 60G device in critical paths

In idle times 60G device can enter deep sleep and turn off
its XTAL clock.
Host access triggers the device power-up flow which will hold
the AHB during XTAL stabilization until device switches from
slow-clock to XTAL clock.
This behavior can stall the PCIe bus for some arbitrary period
of time.
In order to prevent this stall, host can vote for High Latency
Access Policy (HALP) before reading from PCIe bus.
This vote will wakeup the device from deep sleep and prevent
deep sleep until unvote is done.

Signed-off-by: Maya Erez <qca_merez@qca.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

1 files changed, 65 insertions, 15 deletions

diff --git a/drivers/net/wireless/ath/wil6210/interrupt.c b/drivers/net/wireless/ath/wil6210/interrupt.c
index 22592f338c1e..011e7412dcc0 100644
--- a/drivers/net/wireless/ath/wil6210/interrupt.c
+++ b/drivers/net/wireless/ath/wil6210/interrupt.c
@@ -35,17 +35,19 @@
  *
  */
 
-#define WIL6210_IRQ_DISABLE	(0xFFFFFFFFUL)
+#define WIL6210_IRQ_DISABLE		(0xFFFFFFFFUL)
+#define WIL6210_IRQ_DISABLE_NO_HALP	(0xF7FFFFFFUL)
 #define WIL6210_IMC_RX		(BIT_DMA_EP_RX_ICR_RX_DONE | \
 				 BIT_DMA_EP_RX_ICR_RX_HTRSH)
 #define WIL6210_IMC_RX_NO_RX_HTRSH (WIL6210_IMC_RX & \
 				    (~(BIT_DMA_EP_RX_ICR_RX_HTRSH)))
 #define WIL6210_IMC_TX		(BIT_DMA_EP_TX_ICR_TX_DONE | \
 				BIT_DMA_EP_TX_ICR_TX_DONE_N(0))
-#define WIL6210_IMC_MISC	(ISR_MISC_FW_READY | \
-				 ISR_MISC_MBOX_EVT | \
-				 ISR_MISC_FW_ERROR)
-
+#define WIL6210_IMC_MISC_NO_HALP	(ISR_MISC_FW_READY | \
+					 ISR_MISC_MBOX_EVT | \
+					 ISR_MISC_FW_ERROR)
+#define WIL6210_IMC_MISC		(WIL6210_IMC_MISC_NO_HALP | \
+					 BIT_DMA_EP_MISC_ICR_HALP)
 #define WIL6210_IRQ_PSEUDO_MASK (u32)(~(BIT_DMA_PSEUDO_CAUSE_RX | \
 					BIT_DMA_PSEUDO_CAUSE_TX | \
 					BIT_DMA_PSEUDO_CAUSE_MISC))
@@ -53,6 +55,7 @@
 #if defined(CONFIG_WIL6210_ISR_COR)
 /* configure to Clear-On-Read mode */
 #define WIL_ICR_ICC_VALUE	(0xFFFFFFFFUL)
+#define WIL_ICR_ICC_MISC_VALUE	(0xF7FFFFFFUL)
 
 static inline void wil_icr_clear(u32 x, void __iomem *addr)
 {
@@ -60,6 +63,7 @@ static inline void wil_icr_clear(u32 x, void __iomem *addr)
 #else /* defined(CONFIG_WIL6210_ISR_COR) */
 /* configure to Write-1-to-Clear mode */
 #define WIL_ICR_ICC_VALUE	(0UL)
+#define WIL_ICR_ICC_MISC_VALUE	(0UL)
 
 static inline void wil_icr_clear(u32 x, void __iomem *addr)
 {
@@ -88,10 +92,21 @@ static void wil6210_mask_irq_rx(struct wil6210_priv *wil)
 	      WIL6210_IRQ_DISABLE);
 }
 
-static void wil6210_mask_irq_misc(struct wil6210_priv *wil)
+static void wil6210_mask_irq_misc(struct wil6210_priv *wil, bool mask_halp)
 {
+	wil_dbg_irq(wil, "%s: mask_halp(%s)\n", __func__,
+		    mask_halp ? "true" : "false");
+
 	wil_w(wil, RGF_DMA_EP_MISC_ICR + offsetof(struct RGF_ICR, IMS),
-	      WIL6210_IRQ_DISABLE);
+	      mask_halp ? WIL6210_IRQ_DISABLE : WIL6210_IRQ_DISABLE_NO_HALP);
+}
+
+static void wil6210_mask_halp(struct wil6210_priv *wil)
+{
+	wil_dbg_irq(wil, "%s()\n", __func__);
+
+	wil_w(wil, RGF_DMA_EP_MISC_ICR + offsetof(struct RGF_ICR, IMS),
+	      BIT_DMA_EP_MISC_ICR_HALP);
 }
 
 static void wil6210_mask_irq_pseudo(struct wil6210_priv *wil)
@@ -117,10 +132,21 @@ void wil6210_unmask_irq_rx(struct wil6210_priv *wil)
 	      unmask_rx_htrsh ? WIL6210_IMC_RX : WIL6210_IMC_RX_NO_RX_HTRSH);
 }
 
-static void wil6210_unmask_irq_misc(struct wil6210_priv *wil)
+static void wil6210_unmask_irq_misc(struct wil6210_priv *wil, bool unmask_halp)
 {
+	wil_dbg_irq(wil, "%s: unmask_halp(%s)\n", __func__,
+		    unmask_halp ? "true" : "false");
+
 	wil_w(wil, RGF_DMA_EP_MISC_ICR + offsetof(struct RGF_ICR, IMC),
-	      WIL6210_IMC_MISC);
+	      unmask_halp ? WIL6210_IMC_MISC : WIL6210_IMC_MISC_NO_HALP);
+}
+
+static void wil6210_unmask_halp(struct wil6210_priv *wil)
+{
+	wil_dbg_irq(wil, "%s()\n", __func__);
+
+	wil_w(wil, RGF_DMA_EP_MISC_ICR + offsetof(struct RGF_ICR, IMC),
+	      BIT_DMA_EP_MISC_ICR_HALP);
 }
 
 static void wil6210_unmask_irq_pseudo(struct wil6210_priv *wil)
@@ -138,7 +164,7 @@ void wil_mask_irq(struct wil6210_priv *wil)
 
 	wil6210_mask_irq_tx(wil);
 	wil6210_mask_irq_rx(wil);
-	wil6210_mask_irq_misc(wil);
+	wil6210_mask_irq_misc(wil, true);
 	wil6210_mask_irq_pseudo(wil);
 }
 
@@ -151,12 +177,12 @@ void wil_unmask_irq(struct wil6210_priv *wil)
 	wil_w(wil, RGF_DMA_EP_TX_ICR + offsetof(struct RGF_ICR, ICC),
 	      WIL_ICR_ICC_VALUE);
 	wil_w(wil, RGF_DMA_EP_MISC_ICR + offsetof(struct RGF_ICR, ICC),
-	      WIL_ICR_ICC_VALUE);
+	      WIL_ICR_ICC_MISC_VALUE);
 
 	wil6210_unmask_irq_pseudo(wil);
 	wil6210_unmask_irq_tx(wil);
 	wil6210_unmask_irq_rx(wil);
-	wil6210_unmask_irq_misc(wil);
+	wil6210_unmask_irq_misc(wil, true);
 }
 
 void wil_configure_interrupt_moderation(struct wil6210_priv *wil)
@@ -345,7 +371,7 @@ static irqreturn_t wil6210_irq_misc(int irq, void *cookie)
 		return IRQ_NONE;
 	}
 
-	wil6210_mask_irq_misc(wil);
+	wil6210_mask_irq_misc(wil, false);
 
 	if (isr & ISR_MISC_FW_ERROR) {
 		u32 fw_assert_code = wil_r(wil, RGF_FW_ASSERT_CODE);
@@ -373,12 +399,19 @@ static irqreturn_t wil6210_irq_misc(int irq, void *cookie)
 		isr &= ~ISR_MISC_FW_READY;
 	}
 
+	if (isr & BIT_DMA_EP_MISC_ICR_HALP) {
+		wil_dbg_irq(wil, "%s: HALP IRQ invoked\n", __func__);
+		wil6210_mask_halp(wil);
+		isr &= ~BIT_DMA_EP_MISC_ICR_HALP;
+		complete(&wil->halp.comp);
+	}
+
 	wil->isr_misc = isr;
 
 	if (isr) {
 		return IRQ_WAKE_THREAD;
 	} else {
-		wil6210_unmask_irq_misc(wil);
+		wil6210_unmask_irq_misc(wil, false);
 		return IRQ_HANDLED;
 	}
 }
@@ -415,7 +448,7 @@ static irqreturn_t wil6210_irq_misc_thread(int irq, void *cookie)
 
 	wil->isr_misc = 0;
 
-	wil6210_unmask_irq_misc(wil);
+	wil6210_unmask_irq_misc(wil, false);
 
 	return IRQ_HANDLED;
 }
@@ -557,6 +590,23 @@ void wil6210_clear_irq(struct wil6210_priv *wil)
 	wmb(); /* make sure write completed */
 }
 
+void wil6210_set_halp(struct wil6210_priv *wil)
+{
+	wil_dbg_misc(wil, "%s()\n", __func__);
+
+	wil_w(wil, RGF_DMA_EP_MISC_ICR + offsetof(struct RGF_ICR, ICS),
+	      BIT_DMA_EP_MISC_ICR_HALP);
+}
+
+void wil6210_clear_halp(struct wil6210_priv *wil)
+{
+	wil_dbg_misc(wil, "%s()\n", __func__);
+
+	wil_w(wil, RGF_DMA_EP_MISC_ICR + offsetof(struct RGF_ICR, ICR),
+	      BIT_DMA_EP_MISC_ICR_HALP);
+	wil6210_unmask_halp(wil);
+}
+
 int wil6210_init_irq(struct wil6210_priv *wil, int irq, bool use_msi)
 {
 	int rc;