[PATCH v2 1/3] mtd: nand: lpc32xx_slc: improve SLCTAC_*() macro definitions
Vladimir Zapolskiy
vz at mleia.com
Wed Sep 30 16:23:35 PDT 2015
No functional change, move bitfield calculations to macro
definitions with added clock rate argument, which are in turn defined
by new common SLCTAC_CLOCKS(c, n, s) macro definition.
Signed-off-by: Vladimir Zapolskiy <vz at mleia.com>
---
Changes from v1 to v2:
* none, new change
drivers/mtd/nand/lpc32xx_slc.c | 27 +++++++++++++++------------
1 file changed, 15 insertions(+), 12 deletions(-)
diff --git a/drivers/mtd/nand/lpc32xx_slc.c b/drivers/mtd/nand/lpc32xx_slc.c
index abfec13..9ac0f3b 100644
--- a/drivers/mtd/nand/lpc32xx_slc.c
+++ b/drivers/mtd/nand/lpc32xx_slc.c
@@ -94,22 +94,25 @@
/**********************************************************************
* slc_tac register definitions
**********************************************************************/
+/* Computation of clock cycles on basis of controller and device clock rates */
+#define SLCTAC_CLOCKS(c, n, s) (((1 + (c / n)) & 0xF) << s)
+
/* Clock setting for RDY write sample wait time in 2*n clocks */
#define SLCTAC_WDR(n) (((n) & 0xF) << 28)
/* Write pulse width in clock cycles, 1 to 16 clocks */
-#define SLCTAC_WWIDTH(n) (((n) & 0xF) << 24)
+#define SLCTAC_WWIDTH(c, n) (SLCTAC_CLOCKS(c, n, 24))
/* Write hold time of control and data signals, 1 to 16 clocks */
-#define SLCTAC_WHOLD(n) (((n) & 0xF) << 20)
+#define SLCTAC_WHOLD(c, n) (SLCTAC_CLOCKS(c, n, 20))
/* Write setup time of control and data signals, 1 to 16 clocks */
-#define SLCTAC_WSETUP(n) (((n) & 0xF) << 16)
+#define SLCTAC_WSETUP(c, n) (SLCTAC_CLOCKS(c, n, 16))
/* Clock setting for RDY read sample wait time in 2*n clocks */
#define SLCTAC_RDR(n) (((n) & 0xF) << 12)
/* Read pulse width in clock cycles, 1 to 16 clocks */
-#define SLCTAC_RWIDTH(n) (((n) & 0xF) << 8)
+#define SLCTAC_RWIDTH(c, n) (SLCTAC_CLOCKS(c, n, 8))
/* Read hold time of control and data signals, 1 to 16 clocks */
-#define SLCTAC_RHOLD(n) (((n) & 0xF) << 4)
+#define SLCTAC_RHOLD(c, n) (SLCTAC_CLOCKS(c, n, 4))
/* Read setup time of control and data signals, 1 to 16 clocks */
-#define SLCTAC_RSETUP(n) (((n) & 0xF) << 0)
+#define SLCTAC_RSETUP(c, n) (SLCTAC_CLOCKS(c, n, 0))
/**********************************************************************
* slc_ecc register definitions
@@ -240,13 +243,13 @@ static void lpc32xx_nand_setup(struct lpc32xx_nand_host *host)
/* Compute clock setup values */
tmp = SLCTAC_WDR(host->ncfg->wdr_clks) |
- SLCTAC_WWIDTH(1 + (clkrate / host->ncfg->wwidth)) |
- SLCTAC_WHOLD(1 + (clkrate / host->ncfg->whold)) |
- SLCTAC_WSETUP(1 + (clkrate / host->ncfg->wsetup)) |
+ SLCTAC_WWIDTH(clkrate, host->ncfg->wwidth) |
+ SLCTAC_WHOLD(clkrate, host->ncfg->whold) |
+ SLCTAC_WSETUP(clkrate, host->ncfg->wsetup) |
SLCTAC_RDR(host->ncfg->rdr_clks) |
- SLCTAC_RWIDTH(1 + (clkrate / host->ncfg->rwidth)) |
- SLCTAC_RHOLD(1 + (clkrate / host->ncfg->rhold)) |
- SLCTAC_RSETUP(1 + (clkrate / host->ncfg->rsetup));
+ SLCTAC_RWIDTH(clkrate, host->ncfg->rwidth) |
+ SLCTAC_RHOLD(clkrate, host->ncfg->rhold) |
+ SLCTAC_RSETUP(clkrate, host->ncfg->rsetup);
writel(tmp, SLC_TAC(host->io_base));
}
--
2.1.4
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