[PATCH V2 3/6] mtd: bcm47xxnflash: init NAND on BCM4706

Rafał Miłecki
2012-11-12T12:03:41Z

drivers/mtd/nand/bcm47xxnflash/Makefile | 1 +
drivers/mtd/nand/bcm47xxnflash/ops_bcm4706.c | 109 ++++++++++++++++++++++++++
2 files changed, 110 insertions(+), 0 deletions(-)
create mode 100644 drivers/mtd/nand/bcm47xxnflash/ops_bcm4706.c

diff --git a/drivers/mtd/nand/bcm47xxnflash/Makefile b/drivers/mtd/nand/bcm47xxnflash/Makefile
index 1d0693a..4f688f9 100644
--- a/drivers/mtd/nand/bcm47xxnflash/Makefile
+++ b/drivers/mtd/nand/bcm47xxnflash/Makefile
@@ -1,3 +1,4 @@
bcm47xxnflash-y += main.o
+bcm47xxnflash- += ops_bcm4706.o

obj-$(CONFIG_MTD_NAND_BCM47XXNFLASH) += bcm47xxnflash.o
diff --git a/drivers/mtd/nand/bcm47xxnflash/ops_bcm4706.c b/drivers/mtd/nand/bcm47xxnflash/ops_bcm4706.c
new file mode 100644
index 0000000..ae8a793
--- /dev/null
+++ b/drivers/mtd/nand/bcm47xxnflash/ops_bcm4706.c
@@ -0,0 +1,109 @@
+/*
+ * BCM47XX NAND flash driver
+ *
+ * Copyright (C) 2012 Rafał Miłecki <zajec5@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/bcma/bcma.h>
+
+#include "bcm47xxnflash.h"
+
+/**************************************************
+ * Various helpers
+ **************************************************/
+
+static inline u8 bcm47xxnflash_ops_bcm4706_ns_to_cycle(u16 ns, u16 clock)
+{
+ return ((ns * 1000 * clock) / 1000000) + 1;
+}
+
+/**************************************************
+ * NAND chip ops
+ **************************************************/
+
+/* Default nand_select_chip calls cmd_ctrl, which is not used in BCM4706 */
+static void bcm47xxnflash_ops_bcm4706_select_chip(struct mtd_info *mtd,
+ int chip)
+{
+ return;
+}
+
+/**************************************************
+ * Init
+ **************************************************/
+
+int bcm47xxnflash_ops_bcm4706_init(struct bcm47xxnflash *b47n)
+{
+ int err;
+ u32 freq;
+ u16 clock;
+ u8 w0, w1, w2, w3, w4;
+
+ unsigned long chipsize; /* MiB */
+ u8 tbits, col_bits, col_size, row_bits, row_bsize;
+ u32 val;
+
+ b47n->nand_chip.select_chip = bcm47xxnflash_ops_bcm4706_select_chip;
+ b47n->nand_chip.ecc.mode = NAND_ECC_NONE; /* TODO: implement ECC */
+
+ /* Enable NAND flash access */
+ bcma_cc_set32(b47n->cc, BCMA_CC_4706_FLASHSCFG,
+ BCMA_CC_4706_FLASHSCFG_NF1);
+
+ /* Configure wait counters */
+ if (b47n->cc->status & BCMA_CC_CHIPST_4706_PKG_OPTION) {
+ freq = 100000000;
+ } else {
+ freq = bcma_chipco_pll_read(b47n->cc, 4);
+ freq = (freq * 0xFFF) >> 3;
+ freq = (freq * 25000000) >> 3;
+ }
+ clock = freq / 1000000;
+ w0 = bcm47xxnflash_ops_bcm4706_ns_to_cycle(15, clock);
+ w1 = bcm47xxnflash_ops_bcm4706_ns_to_cycle(20, clock);
+ w2 = bcm47xxnflash_ops_bcm4706_ns_to_cycle(10, clock);
+ w3 = bcm47xxnflash_ops_bcm4706_ns_to_cycle(10, clock);
+ w4 = bcm47xxnflash_ops_bcm4706_ns_to_cycle(100, clock);
+ bcma_cc_write32(b47n->cc, BCMA_CC_NFLASH_WAITCNT0,
+ (w4 << 24 | w3 << 18 | w2 << 12 | w1 << 6 | w0));
+
+ /* Scan NAND */
+ err = nand_scan(&b47n->mtd, 1);
+ if (err) {
+ pr_err("Could not scan NAND flash: %d\n", err);
+ goto exit;
+ }
+
+ /* Configure FLASH */
+ chipsize = b47n->nand_chip.chipsize >> 20;
+ tbits = ffs(chipsize); /* find first bit set */
+ if (!tbits || tbits != fls(chipsize)) {
+ pr_err("Invalid flash size: 0x%lX\n", chipsize);
+ err = -ENOTSUPP;
+ goto exit;
+ }
+ tbits += 19; /* Broadcom increases *index* by 20, we increase *pos* */
+
+ col_bits = b47n->nand_chip.page_shift + 1;
+ col_size = (col_bits + 7) / 8;
+
+ row_bits = tbits - col_bits + 1;
+ row_bsize = (row_bits + 7) / 8;
+
+ val = ((row_bsize - 1) << 6) | ((col_size - 1) << 4) | 2;
+ bcma_cc_write32(b47n->cc, BCMA_CC_NFLASH_CONF, val);
+
+exit:
+ if (err)
+ bcma_cc_mask32(b47n->cc, BCMA_CC_4706_FLASHSCFG,
+ ~BCMA_CC_4706_FLASHSCFG_NF1);
+ return err;
+}
--
1.7.7