BYT: byt_irq_handler() is entered multiple times for a single IPC interrupt

[keyonjie]

On BYT, byt_irq_handler() is entered multiple times for a single IPC interrupt, as we don't mask the interrupt in time in the handler.

experiment patch and dmesg attached below:

diff --git a/sound/soc/sof/intel/byt.c b/sound/soc/sof/intel/byt.c
index 2abf80b3eb52..307b4a03f4c5 100644
--- a/sound/soc/sof/intel/byt.c
+++ b/sound/soc/sof/intel/byt.c
@@ -189,6 +189,7 @@ static irqreturn_t byt_irq_handler(int irq, void *context)
 
        /* Interrupt arrived, check src */
        isr = snd_sof_dsp_read64(sdev, BYT_DSP_BAR, SHIM_ISRX);
+       printk(KERN_DEBUG "Keyon: %s, %d, isr:0x%llx\n", __func__, __LINE__, isr);
        if (isr & (SHIM_ISRX_DONE | SHIM_ISRX_BUSY))
                ret = IRQ_WAKE_THREAD;
 
@@ -203,10 +204,15 @@ static irqreturn_t byt_irq_thread(int irq, void *context)
 
        imrx = snd_sof_dsp_read64(sdev, BYT_DSP_BAR, SHIM_IMRX);
        ipcx = snd_sof_dsp_read64(sdev, BYT_DSP_BAR, SHIM_IPCX);
+       ipcd = snd_sof_dsp_read64(sdev, BYT_DSP_BAR, SHIM_IPCD);
+
+       printk(KERN_DEBUG "Keyon: %s, %d, imrx:0x%llx, ipcx:0x%llx, ipcd:0x%llx\n",
+              __func__, __LINE__, imrx, ipcx, ipcd);
 
        /* reply message from DSP */
        if (ipcx & SHIM_BYT_IPCX_DONE &&
            !(imrx & SHIM_IMRX_DONE)) {
+               printk(KERN_DEBUG "Keyon: %s, %d\n", __func__, __LINE__);
                /* Mask Done interrupt before first */
                snd_sof_dsp_update_bits64_unlocked(sdev, BYT_DSP_BAR,
                                                   SHIM_IMRX,
@@ -231,9 +237,9 @@ static irqreturn_t byt_irq_thread(int irq, void *context)
        }
 
        /* new message from DSP */
-       ipcd = snd_sof_dsp_read64(sdev, BYT_DSP_BAR, SHIM_IPCD);
        if (ipcd & SHIM_BYT_IPCD_BUSY &&
            !(imrx & SHIM_IMRX_BUSY)) {
+               printk(KERN_DEBUG "Keyon: %s, %d\n", __func__, __LINE__);
                /* Mask Busy interrupt before return */
                snd_sof_dsp_update_bits64_unlocked(sdev, BYT_DSP_BAR,
                                                   SHIM_IMRX,

dmesg logs during set volume IPC as below:

[    9.602493] sof-audio-acpi 808622A8:00: ipc tx: 0x50010000
[    9.602545] Keyon: byt_irq_handler, 192, isr:0x1
[    9.602592] Keyon: byt_irq_handler, 192, isr:0x1
[    9.602605] Keyon: byt_irq_thread, 210, imrx:0x0, ipcx:0x4000000000000000, ipcd:0x0
[    9.602609] Keyon: byt_irq_handler, 192, isr:0x1
[    9.602617] Keyon: byt_irq_thread, 215
[    9.602626] Keyon: byt_irq_handler, 192, isr:0x1
[    9.602687] Keyon: byt_irq_thread, 210, imrx:0x0, ipcx:0x0, ipcd:0x0
[    9.602699] sof-audio-acpi 808622A8:00: ipc tx succeeded: 0x50010000
[    9.602773] sof-audio-acpi 808622A8:00: ipc tx: 0x50010000
[    9.602884] Keyon: byt_irq_handler, 192, isr:0x1
[    9.602950] Keyon: byt_irq_handler, 192, isr:0x1
[    9.602971] Keyon: byt_irq_handler, 192, isr:0x1
[    9.602983] Keyon: byt_irq_thread, 210, imrx:0x0, ipcx:0x4000000000000000, ipcd:0x0
[    9.602986] Keyon: byt_irq_thread, 215
[    9.602997] Keyon: byt_irq_handler, 192, isr:0x1
[    9.603054] Keyon: byt_irq_thread, 210, imrx:0x0, ipcx:0x0, ipcd:0x0

[plbossart]

fixed now