@@ -7,6 +7,10 @@ Required properties:
- interrupts : The interrupt number.
- dm-mask : DMA bit mask
+Optional properties:
+ - max-banks : Maximum number of banks supported by hardware. If not
+ specified, it is determined based on the "features" register of hardware.
+
The device tree may optionally contain sub-nodes describing partitions of the
address space. See partition.txt for more detail.
@@ -1353,7 +1353,8 @@ static void denali_hw_init(struct denali_nand_info *denali)
*/
denali->bbtskipbytes = ioread32(denali->flash_reg +
SPARE_AREA_SKIP_BYTES);
- detect_max_banks(denali);
+ if (!denali->max_banks)
+ detect_max_banks(denali);
denali_nand_reset(denali);
iowrite32(0x0F, denali->flash_reg + RB_PIN_ENABLED);
iowrite32(CHIP_EN_DONT_CARE__FLAG,
@@ -85,6 +85,9 @@ static int denali_dt_probe(struct platform_device *ofdev)
denali->dev->dma_mask = NULL;
}
+ of_property_read_u32(ofdev->dev.of_node, "max-banks",
+ &denali->max_banks);
+
dt->clk = devm_clk_get(&ofdev->dev, NULL);
if (IS_ERR(dt->clk)) {
dev_err(&ofdev->dev, "no clk available\n");
Commit 271707b1d817 ("mtd: nand: denali: max_banks calculation changed in revision 5.1") supported the new encoding of the "n_banks" bits of the "features" register, but there is an unfortunate case not covered by that commit. Panasonic (its System LSI Business Division is now Socionext) bought a couple of versions of this IP. The IP released for Panasonic around Feb. 2012 is revision 5 and uses the old encoding for n_banks (2 << n_banks). While the one released around Nov. 2012 is also revision 5, but it uses the new encoding (1 << n_banks). The revision register cannot distinguish these two incompatible hardware. I guess this IP series is not well-organized. I could not find any solution but giving max_banks from DT property. This commit works around the problem by allowing DT to set the max_banks forcibly. Of course, this DT property can be optional if the auto detection based on the hardware registers works well. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Acked-by: Rob Herring <robh@kernel.org> --- Changes in v2: - rebase on v4.6-rc1 - add Rob's Acked-by - Rephrase git-log slightly Documentation/devicetree/bindings/mtd/denali-nand.txt | 4 ++++ drivers/mtd/nand/denali.c | 3 ++- drivers/mtd/nand/denali_dt.c | 3 +++ 3 files changed, 9 insertions(+), 1 deletion(-) -- 1.9.1 ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/