Commit e16eceea authored by Olga Kitaina's avatar Olga Kitaina Committed by Miquel Raynal
Browse files

mtd: rawnand: arasan: Fix clock rate in NV-DDR 



According to the Arasan NAND controller spec, the flash clock rate for SDR
must be <= 100 MHz, while for NV-DDR it must be the same as the rate of the
CLK line for the mode. The driver previously always set 100 MHz for NV-DDR,
which would result in incorrect behavior for NV-DDR modes 0-4.

The appropriate clock rate can be calculated from the NV-DDR timing
parameters as 1/tCK, or for rates measured in picoseconds,
10^12 / nand_nvddr_timings->tCK_min.

Fixes: 197b88fe ("mtd: rawnand: arasan: Add new Arasan NAND controller")
CC: stable@vger.kernel.org # 5.8+
Signed-off-by: default avatarOlga Kitaina <okitain@gmail.com>
Signed-off-by: default avatarAmit Kumar Mahapatra <amit.kumar-mahapatra@xilinx.com>
Signed-off-by: default avatarMiquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20220628154824.12222-3-amit.kumar-mahapatra@xilinx.com
parent 7499bfee

drivers/mtd/nand/raw/arasan-nand-controller.c

+7 −1
Original line number Diff line number Diff line
@@ -1043,7 +1043,13 @@ static int anfc_setup_interface(struct nand_chip *chip, int target, 
				 DQS_BUFF_SEL_OUT(dqs_mode);

	}



	if (nand_interface_is_sdr(conf)) {

		anand->clk = ANFC_XLNX_SDR_DFLT_CORE_CLK;

	} else {

		/* ONFI timings are defined in picoseconds */

		anand->clk = div_u64((u64)NSEC_PER_SEC * 1000,

				     conf->timings.nvddr.tCK_min);

	}



	/*

	 * Due to a hardware bug in the ZynqMP SoC, SDR timing modes 0-1 work