ASoC: Intel: mrfld - add shim save restore

In ACPI platform we need to save few registers of Shim on suspend and
restore them on resume, so add handlers to do this

Signed-off-by: Subhransu S. Prusty <subhransu.s.prusty@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/intel/sst/sst.c

@@ -339,6 +339,34 @@ void sst_context_cleanup(struct intel_sst_drv *ctx)
 }
 EXPORT_SYMBOL_GPL(sst_context_cleanup);
 
+static inline void sst_save_shim64(struct intel_sst_drv *ctx,
+			    void __iomem *shim,
+			    struct sst_shim_regs64 *shim_regs)
+{
+	unsigned long irq_flags;
+
+	spin_lock_irqsave(&ctx->ipc_spin_lock, irq_flags);
+
+	shim_regs->imrx = sst_shim_read64(shim, SST_IMRX),
+
+	spin_unlock_irqrestore(&ctx->ipc_spin_lock, irq_flags);
+}
+
+static inline void sst_restore_shim64(struct intel_sst_drv *ctx,
+				      void __iomem *shim,
+				      struct sst_shim_regs64 *shim_regs)
+{
+	unsigned long irq_flags;
+
+	/*
+	 * we only need to restore IMRX for this case, rest will be
+	 * initialize by FW or driver when firmware is loaded
+	 */
+	spin_lock_irqsave(&ctx->ipc_spin_lock, irq_flags);
+	sst_shim_write64(shim, SST_IMRX, shim_regs->imrx),
+	spin_unlock_irqrestore(&ctx->ipc_spin_lock, irq_flags);
+}
+
 void sst_configure_runtime_pm(struct intel_sst_drv *ctx)
 {
 	pm_runtime_set_autosuspend_delay(ctx->dev, SST_SUSPEND_DELAY);