ddr: socfpga: Fix EMIF clear timeout

The current EMIF clear timeout handling code was applying bitwise
operations to signed data types and as it was, was extremely hard
to read. Replace it with simple wait_for_bit(). Expand the error
handling to make it more readable too.

This patch also changes the timeout for emif_clear() from 14 hours
to 1 second.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Chin Liang See <chin.liang.see@intel.com>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Simon Goldschmidt <simon.k.r.goldschmidt@gmail.com>
Cc: Tien Fong Chee <tien.fong.chee@intel.com>

diff --git a/drivers/ddr/altera/sdram_arria10.c b/drivers/ddr/altera/sdram_arria10.c
index be5ce778e8c7e483b264042ae13632d3e7eab033..b450a1b1be0a8f1d439fcbb9499ed761af0d8219 100644 (file)
--- a/drivers/ddr/altera/sdram_arria10.c
+++ b/drivers/ddr/altera/sdram_arria10.c
@@ -31,7 +31,6 @@ static u64 sdram_size_calc(void);
 #define DDR_REG_CORE2SEQ        0xFFD05078
 #define DDR_READ_LATENCY_DELAY 40
 #define DDR_SIZE_2GB_HEX       0x80000000
-#define DDR_MAX_TRIES          0x00100000
 
 #define IO48_MMR_DRAMSTS       0xFFCFA0EC
 #define IO48_MMR_NIOS2_RESERVE0        0xFFCFA110
@@ -133,22 +132,16 @@ static unsigned char ddr_wait_bit(u32 ereg, u32 bit,
 
 static int emif_clear(void)
 {
-       u32 i = DDR_MAX_TRIES;
-       u8 ret = 0;
-
        writel(0, DDR_REG_CORE2SEQ);
 
-       do {
-               ret = !wait_for_bit_le32((u32 *)DDR_REG_SEQ2CORE,
-                                  SEQ2CORE_MASK, 1, 50, 0);
-       } while (ret && (--i > 0));
-
-       return !i;
+       return wait_for_bit_le32((u32 *)DDR_REG_SEQ2CORE,
+                               SEQ2CORE_MASK, 0, 1000, 0);
 }
 
 static int emif_reset(void)
 {
        u32 c2s, s2c;
+       int ret;
 
        c2s = readl(DDR_REG_CORE2SEQ);
        s2c = readl(DDR_REG_SEQ2CORE);
@@ -159,9 +152,12 @@ static int emif_reset(void)
             readl(IO48_MMR_NIOS2_RESERVE2),
             readl(IO48_MMR_DRAMSTS));
 
-       if ((s2c & SEQ2CORE_MASK) && emif_clear()) {
-               debug("failed emif_clear()\n");
-               return -EPERM;
+       if (s2c & SEQ2CORE_MASK) {
+               ret = emif_clear();
+               if (ret) {
+                       debug("failed emif_clear()\n");
+                       return -EPERM;
+               }
        }
 
        writel(CORE2SEQ_INT_REQ, DDR_REG_CORE2SEQ);
@@ -173,7 +169,8 @@ static int emif_reset(void)
                debug("emif_reset interrupt acknowledged\n");
        }
 
-       if (emif_clear()) {
+       ret = emif_clear();
+       if (ret) {
                debug("emif_clear() failed\n");
                return -EPERM;
        }