[PATCH v2 6/9] mtd: gpmi: simplify the setting DLL code
Huang Shijie
b32955 at freescale.com
Thu Sep 13 02:57:57 EDT 2012
The setting DLL code is a little mess.
Just simplify the code and the comments.
Signed-off-by: Huang Shijie <b32955 at freescale.com>
---
drivers/mtd/nand/gpmi-nand/gpmi-lib.c | 22 +++++++++-------------
1 files changed, 9 insertions(+), 13 deletions(-)
diff --git a/drivers/mtd/nand/gpmi-nand/gpmi-lib.c b/drivers/mtd/nand/gpmi-nand/gpmi-lib.c
index 2d1f77c..010665c 100644
--- a/drivers/mtd/nand/gpmi-nand/gpmi-lib.c
+++ b/drivers/mtd/nand/gpmi-nand/gpmi-lib.c
@@ -779,30 +779,26 @@ void gpmi_begin(struct gpmi_nand_data *this)
writel(BM_GPMI_CTRL1_DLL_ENABLE, gpmi_regs + HW_GPMI_CTRL1_CLR);
/* Clear out the DLL control fields. */
- writel(BM_GPMI_CTRL1_RDN_DELAY, gpmi_regs + HW_GPMI_CTRL1_CLR);
- writel(BM_GPMI_CTRL1_HALF_PERIOD, gpmi_regs + HW_GPMI_CTRL1_CLR);
+ reg = BM_GPMI_CTRL1_RDN_DELAY | BM_GPMI_CTRL1_HALF_PERIOD;
+ writel(reg, gpmi_regs + HW_GPMI_CTRL1_CLR);
/* If no sample delay is called for, return immediately. */
if (!hw.sample_delay_factor)
return;
- /* Configure the HALF_PERIOD flag. */
- if (hw.use_half_periods)
- writel(BM_GPMI_CTRL1_HALF_PERIOD,
- gpmi_regs + HW_GPMI_CTRL1_SET);
+ /* Set RDN_DELAY or HALF_PERIOD. */
+ reg = ((hw.use_half_periods) ? BM_GPMI_CTRL1_HALF_PERIOD : 0)
+ | BF_GPMI_CTRL1_RDN_DELAY(hw.sample_delay_factor);
- /* Set the delay factor. */
- writel(BF_GPMI_CTRL1_RDN_DELAY(hw.sample_delay_factor),
- gpmi_regs + HW_GPMI_CTRL1_SET);
+ writel(reg, gpmi_regs + HW_GPMI_CTRL1_SET);
- /* Enable the DLL. */
+ /* At last, we enable the DLL. */
writel(BM_GPMI_CTRL1_DLL_ENABLE, gpmi_regs + HW_GPMI_CTRL1_SET);
/*
* After we enable the GPMI DLL, we have to wait 64 clock cycles before
- * we can use the GPMI.
- *
- * Calculate the amount of time we need to wait, in microseconds.
+ * we can use the GPMI. Calculate the amount of time we need to wait,
+ * in microseconds.
*/
clock_period_in_ns = NSEC_PER_SEC / clk_get_rate(r->clock[0]);
dll_wait_time_in_us = (clock_period_in_ns * 64) / 1000;
--
1.7.0.4
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