mtd: gpmi: add a new field for HW_GPMI_TIMING1

The gpmi_nfc_compute_hardware_timing{} should contains all the
fields setting for gpmi timing registers. It already contains the fields
for HW_GPMI_TIMING0 and HW_GPMI_CTRL1.

So it is better to add a new field setting for HW_GPMI_TIMING1 in
this data structure. This makes the code more clear in logic.

This patch also changes some comments to make the code more readable.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

3 files changed, 22 insertions, 8 deletions

diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-lib.c b/drivers/mtd/nand/gpmi-nand/gpmi-lib.c
index 2289cf8dc35b..c95dbe8bb272 100644
--- a/drivers/mtd/nand/gpmi-nand/gpmi-lib.c
+++ b/drivers/mtd/nand/gpmi-nand/gpmi-lib.c
@@ -728,6 +728,7 @@ return_results:
         hw->address_setup_in_cycles = address_setup_in_cycles;
         hw->use_half_periods        = dll_use_half_periods;
         hw->sample_delay_factor     = sample_delay_factor;
+        hw->device_busy_timeout     = GPMI_DEFAULT_BUSY_TIMEOUT;
 
         /* Return success. */
         return 0;
@@ -752,26 +753,26 @@ void gpmi_begin(struct gpmi_nand_data *this)
                 goto err_out;
         }
 
-        /* set ready/busy timeout */
-        writel(0x500 << BP_GPMI_TIMING1_BUSY_TIMEOUT,
-                gpmi_regs + HW_GPMI_TIMING1);
-
         /* Get the timing information we need. */
         nfc->clock_frequency_in_hz = clk_get_rate(r->clock[0]);
         clock_period_in_ns = 1000000000 / nfc->clock_frequency_in_hz;
 
         gpmi_nfc_compute_hardware_timing(this, &hw);
 
-        /* Set up all the simple timing parameters. */
+        /* [1] Set HW_GPMI_TIMING0 */
         reg = BF_GPMI_TIMING0_ADDRESS_SETUP(hw.address_setup_in_cycles) |
                 BF_GPMI_TIMING0_DATA_HOLD(hw.data_hold_in_cycles)         |
                 BF_GPMI_TIMING0_DATA_SETUP(hw.data_setup_in_cycles)       ;
 
         writel(reg, gpmi_regs + HW_GPMI_TIMING0);
 
-        /*
-         * DLL_ENABLE must be set to 0 when setting RDN_DELAY or HALF_PERIOD.
-         */
+        /* [2] Set HW_GPMI_TIMING1 */
+        writel(BF_GPMI_TIMING1_BUSY_TIMEOUT(hw.device_busy_timeout),
+                gpmi_regs + HW_GPMI_TIMING1);
+
+        /* [3] The following code is to set the HW_GPMI_CTRL1. */
+
+        /* DLL_ENABLE must be set to 0 when setting RDN_DELAY or HALF_PERIOD. */
         writel(BM_GPMI_CTRL1_DLL_ENABLE, gpmi_regs + HW_GPMI_CTRL1_CLR);
 
         /* Clear out the DLL control fields. */
diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-nand.h b/drivers/mtd/nand/gpmi-nand/gpmi-nand.h
index 1f6121782330..c814bddaffc4 100644
--- a/drivers/mtd/nand/gpmi-nand/gpmi-nand.h
+++ b/drivers/mtd/nand/gpmi-nand/gpmi-nand.h
@@ -189,14 +189,24 @@ struct gpmi_nand_data {
  * @data_setup_in_cycles:      The data setup time, in cycles.
  * @data_hold_in_cycles:       The data hold time, in cycles.
  * @address_setup_in_cycles:   The address setup time, in cycles.
+ * @device_busy_timeout:       The timeout waiting for NAND Ready/Busy,
+ *                             this value is the number of cycles multiplied
+ *                             by 4096.
  * @use_half_periods:          Indicates the clock is running slowly, so the
  *                             NFC DLL should use half-periods.
  * @sample_delay_factor:       The sample delay factor.
  */
 struct gpmi_nfc_hardware_timing {
+        /* for HW_GPMI_TIMING0 */
         uint8_t  data_setup_in_cycles;
         uint8_t  data_hold_in_cycles;
         uint8_t  address_setup_in_cycles;
+
+        /* for HW_GPMI_TIMING1 */
+        uint16_t device_busy_timeout;
+#define GPMI_DEFAULT_BUSY_TIMEOUT       0x500 /* default busy timeout value.*/
+
+        /* for HW_GPMI_CTRL1 */
         bool     use_half_periods;
         uint8_t  sample_delay_factor;
 };
diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-regs.h b/drivers/mtd/nand/gpmi-nand/gpmi-regs.h
index 83431240e2f2..8994e201924c 100644
--- a/drivers/mtd/nand/gpmi-nand/gpmi-regs.h
+++ b/drivers/mtd/nand/gpmi-nand/gpmi-regs.h
@@ -154,6 +154,9 @@
 
 #define HW_GPMI_TIMING1                                 0x00000080
 #define BP_GPMI_TIMING1_BUSY_TIMEOUT                    16
+#define BM_GPMI_TIMING1_BUSY_TIMEOUT    (0xffff << BP_GPMI_TIMING1_BUSY_TIMEOUT)
+#define BF_GPMI_TIMING1_BUSY_TIMEOUT(v)         \
+        (((v) << BP_GPMI_TIMING1_BUSY_TIMEOUT) & BM_GPMI_TIMING1_BUSY_TIMEOUT)
 
 #define HW_GPMI_TIMING2                                 0x00000090
 #define HW_GPMI_DATA                                    0x000000a0