mtd: bcm47xxnflash: init NAND on BCM4706

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
This commit is contained in:
Rafał Miłecki 2012-11-12 13:03:22 +01:00 committed by Artem Bityutskiy
parent a5401370c5
commit 19c0921c84
2 changed files with 110 additions and 0 deletions

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@ -1,3 +1,4 @@
bcm47xxnflash-y += main.o
bcm47xxnflash- += ops_bcm4706.o
obj-$(CONFIG_MTD_NAND_BCM47XXNFLASH) += bcm47xxnflash.o

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@ -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;
}