Re: [PATCH 3/3] mtd: nand: add NAND driver for Broadcom STB NAND controller

From: RafaÅ MiÅecki
Date: Sat Mar 07 2015 - 17:15:34 EST


On 7 March 2015 at 02:18, Brian Norris <computersforpeace@xxxxxxxxx> wrote:
> +static int brcmnand_waitfunc(struct mtd_info *mtd, struct nand_chip *this)
> +{
> + struct nand_chip *chip = mtd->priv;
> + struct brcmnand_host *host = chip->priv;
> + struct brcmnand_controller *ctrl = host->ctrl;
> + unsigned long timeo = msecs_to_jiffies(100);
> +
> + dev_dbg(ctrl->dev, "wait on native cmd %d\n", ctrl->cmd_pending);
> + if (ctrl->cmd_pending &&
> + wait_for_completion_timeout(&ctrl->done, timeo) <= 0) {
> + unsigned long cmd = brcmnand_read_reg(ctrl, BRCMNAND_CMD_START)
> + >> brcmnand_cmd_shift(ctrl);
> +
> + dev_err_ratelimited(ctrl->dev,
> + "timeout waiting for command %u (%ld)\n",
> + host->last_cmd, cmd);

I think that using host->last_cmd in the above message is really
misleading. Please consider following:

[ 2.061139] [brcmnand_cmdfunc:1151] command:0x90 native_cmd:0x07
[ 2.067123] brcmstb_nand 18028000.nand: send native cmd 7 addr_lo 0x40
[ 2.168395] brcmstb_nand 18028000.nand: timeout waiting for command 144 (7)
[ 2.175321] brcmstb_nand 18028000.nand: intfc status f0000000
[ 2.181051] nand: device found, Manufacturer ID: 0x92, Chip ID: 0xf1
[ 2.187370] nand: Eon NAND 128MiB 3,3V 8-bit
[ 2.191632] nand: 128 MiB, SLC, erase size: 128 KiB, page size:
2048, OOB size: 64
[ 2.199192] brcmstb_nand 18028000.nand: detected 128MiB total,
128KiB blocks, 2KiB pages, 16B OOB, 8-bit, BCH-8
[ 2.199192]
[ 2.210724] Scanning device for bad blocks
[ 2.214812] brcmstb_nand 18028000.nand: send native cmd 1 addr_lo 0x0
[ 2.318394] brcmstb_nand 18028000.nand: timeout waiting for command 144 (1)

As you can see, first there was a brcmnand_cmdfunc call with 0x90
(NAND_CMD_READID). It was translated into internal command 0x07
(CMD_DEVICE_ID_READ).

Then there was a call to brcmnand_read_by_pio which resulted in
sending internal command 0x01 (CMD_PAGE_READ). This one overwrote
previous command. So the timeout wasn't about 144 (0x90) anymore.

I suggest replacing that with something like
"timeout waiting for internal command 0x%02x\n", cmd
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