intel_scu_ipc: move error check out of the loop

This is small performance optimization of the busy_loop().

While here, use BIT() macro instead of plain integers when check the status.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>

1 files changed, 12 insertions, 13 deletions

diff --git a/drivers/platform/x86/intel_scu_ipc.c b/drivers/platform/x86/intel_scu_ipc.c
index 8938c31be447..e6430a3454cf 100644
--- a/drivers/platform/x86/intel_scu_ipc.c
+++ b/drivers/platform/x86/intel_scu_ipc.c
@@ -176,21 +176,21 @@ static inline u32 ipc_data_readl(u32 offset) /* Read ipc u32 data */
 /* Wait till scu status is busy */
 static inline int busy_loop(void)
 {
-        u32 status = 0;
-        u32 loop_count = 0;
+        u32 status = ipc_read_status();
+        u32 loop_count = 100000;
 
-        status = ipc_read_status();
-        while (status & 1) {
+        /* break if scu doesn't reset busy bit after huge retry */
+        while ((status & BIT(0)) && --loop_count) {
                 udelay(1); /* scu processing time is in few u secods */
                 status = ipc_read_status();
-                loop_count++;
-                /* break if scu doesn't reset busy bit after huge retry */
-                if (loop_count > 100000) {
-                        dev_err(&ipcdev.pdev->dev, "IPC timed out");
-                        return -ETIMEDOUT;
-                }
         }
-        if ((status >> 1) & 1)
+
+        if (status & BIT(0)) {
+                dev_err(&ipcdev.pdev->dev, "IPC timed out");
+                return -ETIMEDOUT;
+        }
+
+        if (status & BIT(1))
                 return -EIO;
 
         return 0;
@@ -208,8 +208,7 @@ static inline int ipc_wait_for_interrupt(void)
         }
 
         status = ipc_read_status();
-
-        if ((status >> 1) & 1)
+        if (status & BIT(1))
                 return -EIO;
 
         return 0;