[PATCH v2 1/3] mtd: rawnand: sunxi: group controller delay tables

[James Hilliard <james.hilliard1@gmail.com>]

The tWB and tRHW timing field encodings are controller properties, but
they currently live in standalone lookup tables.

Group them in a timing descriptor selected through the controller
capability data. Point every existing controller at the legacy values so
this is a pure preparation change.

Cc: stable@vger.kernel.org
Signed-off-by: James Hilliard <james.hilliard1@gmail.com>
---
 drivers/mtd/nand/raw/sunxi_nand.c | 36 ++++++++++++++++++++++++++++--------
 1 file changed, 28 insertions(+), 8 deletions(-)

diff --git a/drivers/mtd/nand/raw/sunxi_nand.c b/drivers/mtd/nand/raw/sunxi_nand.c
index 02647565c8ba..d12cbb3c813c 100644
--- a/drivers/mtd/nand/raw/sunxi_nand.c
+++ b/drivers/mtd/nand/raw/sunxi_nand.c
@@ -237,6 +237,14 @@ struct sunxi_nand_hw_ecc {
 	u32 ecc_ctl;
 };
 
+#define SUNXI_NFC_TIMING_STEPS	4
+
+/* Delay arrays contain internal NDFC clock cycles for field values 0 to 3. */
+struct sunxi_nfc_timings {
+	s32 tWB[SUNXI_NFC_TIMING_STEPS];
+	s32 tRHW[SUNXI_NFC_TIMING_STEPS];
+};
+
 /**
  * struct sunxi_nand_chip - stores NAND chip device related information
  *
@@ -301,6 +309,7 @@ static inline struct sunxi_nand_chip *to_sunxi_nand(struct nand_chip *nand)
  *			bytes to write
  * @nuser_data_tab:	Size of @user_data_len_tab
  * @sram_size:		Size of the NAND controller SRAM
+ * @timings:		Controller timing characteristics
  */
 struct sunxi_nfc_caps {
 	bool has_mdma;
@@ -327,6 +336,7 @@ struct sunxi_nfc_caps {
 	unsigned int nuser_data_tab;
 	unsigned int max_ecc_steps;
 	int sram_size;
+	const struct sunxi_nfc_timings *timings;
 };
 
 /**
@@ -1667,8 +1677,10 @@ static int sunxi_nfc_hw_ecc_write_oob(struct nand_chip *nand, int page)
 	return nand_prog_page_end_op(nand);
 }
 
-static const s32 tWB_lut[] = {6, 12, 16, 20};
-static const s32 tRHW_lut[] = {4, 8, 12, 20};
+static const struct sunxi_nfc_timings sun4i_a10_nfc_timings = {
+	.tWB = { 6, 12, 16, 20 },
+	.tRHW = { 4, 8, 12, 20 },
+};
 
 static int _sunxi_nand_lookup_timing(const s32 *lut, int lut_size, u32 duration,
 		u32 clk_period)
@@ -1693,6 +1705,7 @@ static int sunxi_nfc_setup_interface(struct nand_chip *nand, int csline,
 {
 	struct sunxi_nand_chip *sunxi_nand = to_sunxi_nand(nand);
 	struct sunxi_nfc *nfc = to_sunxi_nfc(sunxi_nand->nand.controller);
+	const struct sunxi_nfc_timings *nfc_timings = nfc->caps->timings;
 	const struct nand_sdr_timings *timings;
 	u32 min_clk_period = 0;
 	s32 tWB, tADL, tWHR, tRHW, tCAD;
@@ -1763,8 +1776,10 @@ static int sunxi_nfc_setup_interface(struct nand_chip *nand, int csline,
 		min_clk_period = DIV_ROUND_UP(timings->tWC_min, 2);
 
 	/* T16 - T19 + tCAD */
-	if (timings->tWB_max > (min_clk_period * 20))
-		min_clk_period = DIV_ROUND_UP(timings->tWB_max, 20);
+	if (timings->tWB_max >
+	    (min_clk_period * nfc_timings->tWB[SUNXI_NFC_TIMING_STEPS - 1]))
+		min_clk_period = DIV_ROUND_UP(timings->tWB_max,
+				nfc_timings->tWB[SUNXI_NFC_TIMING_STEPS - 1]);
 
 	if (timings->tADL_min > (min_clk_period * 32))
 		min_clk_period = DIV_ROUND_UP(timings->tADL_min, 32);
@@ -1772,8 +1787,10 @@ static int sunxi_nfc_setup_interface(struct nand_chip *nand, int csline,
 	if (timings->tWHR_min > (min_clk_period * 32))
 		min_clk_period = DIV_ROUND_UP(timings->tWHR_min, 32);
 
-	if (timings->tRHW_min > (min_clk_period * 20))
-		min_clk_period = DIV_ROUND_UP(timings->tRHW_min, 20);
+	if (timings->tRHW_min >
+	    (min_clk_period * nfc_timings->tRHW[SUNXI_NFC_TIMING_STEPS - 1]))
+		min_clk_period = DIV_ROUND_UP(timings->tRHW_min,
+				nfc_timings->tRHW[SUNXI_NFC_TIMING_STEPS - 1]);
 
 	/*
 	 * In non-EDO, tREA should be less than tRP to guarantee that the
@@ -1789,7 +1806,7 @@ static int sunxi_nfc_setup_interface(struct nand_chip *nand, int csline,
 	if (timings->tREA_max > min_clk_period && !timings->tRLOH_min)
 		min_clk_period = timings->tREA_max;
 
-	tWB  = sunxi_nand_lookup_timing(tWB_lut, timings->tWB_max,
+	tWB  = sunxi_nand_lookup_timing(nfc_timings->tWB, timings->tWB_max,
 					min_clk_period);
 	if (tWB < 0) {
 		dev_err(nfc->dev, "unsupported tWB\n");
@@ -1808,7 +1825,7 @@ static int sunxi_nfc_setup_interface(struct nand_chip *nand, int csline,
 		return -EINVAL;
 	}
 
-	tRHW = sunxi_nand_lookup_timing(tRHW_lut, timings->tRHW_min,
+	tRHW = sunxi_nand_lookup_timing(nfc_timings->tRHW, timings->tRHW_min,
 					min_clk_period);
 	if (tRHW < 0) {
 		dev_err(nfc->dev, "unsupported tRHW\n");
@@ -2595,6 +2612,7 @@ static const struct sunxi_nfc_caps sunxi_nfc_a10_caps = {
 	.nstrengths = ARRAY_SIZE(sunxi_ecc_strengths_a10),
 	.max_ecc_steps = 16,
 	.sram_size = 1024,
+	.timings = &sun4i_a10_nfc_timings,
 };
 
 static const struct sunxi_nfc_caps sunxi_nfc_a23_caps = {
@@ -2617,6 +2635,7 @@ static const struct sunxi_nfc_caps sunxi_nfc_a23_caps = {
 	.nstrengths = ARRAY_SIZE(sunxi_ecc_strengths_a10),
 	.max_ecc_steps = 16,
 	.sram_size = 1024,
+	.timings = &sun4i_a10_nfc_timings,
 };
 
 static const struct sunxi_nfc_caps sunxi_nfc_h616_caps = {
@@ -2641,6 +2660,7 @@ static const struct sunxi_nfc_caps sunxi_nfc_h616_caps = {
 	.nuser_data_tab = ARRAY_SIZE(sunxi_user_data_len_h6),
 	.max_ecc_steps = 32,
 	.sram_size = 8192,
+	.timings = &sun4i_a10_nfc_timings,
 };
 
 static const struct of_device_id sunxi_nfc_ids[] = {

-- 
2.53.0