wil6210: new SW reset

New firmware allows for shorter SW reset procedure.
After SW reset, FW raises "fw done" IRQ, at this
moment mailbox control structures are initialized, driver caches it.

New status bit wil_status_reset_done introduced to track completion
of the reset. It is set by "fw ready" irq, and required for WMI rx flow
to access control structures.

WMI Tx flow protected by other status bit, wil_status_fwready. It can't
be set before wil_status_reset_done is set by design.

Signed-off-by: Vladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/wil6210/interrupt.c b/drivers/net/wireless/ath/wil6210/interrupt.c
index de9b971..e3c1e76 100644
--- a/drivers/net/wireless/ath/wil6210/interrupt.c
+++ b/drivers/net/wireless/ath/wil6210/interrupt.c
@@ -240,6 +240,15 @@
 	kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
 }
 
+static void wil_cache_mbox_regs(struct wil6210_priv *wil)
+{
+	/* make shadow copy of registers that should not change on run time */
+	wil_memcpy_fromio_32(&wil->mbox_ctl, wil->csr + HOST_MBOX,
+			     sizeof(struct wil6210_mbox_ctl));
+	wil_mbox_ring_le2cpus(&wil->mbox_ctl.rx);
+	wil_mbox_ring_le2cpus(&wil->mbox_ctl.tx);
+}
+
 static irqreturn_t wil6210_irq_misc(int irq, void *cookie)
 {
 	struct wil6210_priv *wil = cookie;
@@ -268,6 +277,8 @@
 
 	if (isr & ISR_MISC_FW_READY) {
 		wil_dbg_irq(wil, "IRQ: FW ready\n");
+		wil_cache_mbox_regs(wil);
+		set_bit(wil_status_reset_done, &wil->status);
 		/**
 		 * Actual FW ready indicated by the
 		 * WMI_FW_READY_EVENTID