[PATCH 0/3] Mediatek SPI-NOR flash driver

[PATCH 0/3] Mediatek SPI-NOR flash driver

[Bayi Cheng]

The patch supports MediaTek's NOR flash controller.
The NOR flash controller is specifically for spi nor flash,
and it is more stable and faster than SPI bus, the MTK
NOR controller not only support single mode but also support
dual mode and quad mode.

This series is based on v4.2-rc1 and l2-mtd.git
(git://git.infradead.org/l2-mtd.git)

Bayi Cheng (3):
  doc: dt: add documentation for Mediatek spi-nor controller
  mtd: mtk-nor: mtk serial flash controller driver
  arm64: dts: mt8173: Add nor flash node

 Documentation/devicetree/bindings/mtd/mtk_nor.txt |  25 +
 arch/arm64/boot/dts/mediatek/mt8173.dtsi          |  10 +
 drivers/mtd/spi-nor/Kconfig                       |   7 +
 drivers/mtd/spi-nor/Makefile                      |   1 +
 drivers/mtd/spi-nor/mtk_nor.c                     | 533 ++++++++++++++++++++++
 5 files changed, 576 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mtd/mtk_nor.txt
 create mode 100644 drivers/mtd/spi-nor/mtk_nor.c

--
1.8.1.1.dirty

[PATCH 1/3] doc: dt: add documentation for Mediatek spi-nor controller

[Bayi Cheng]

Add device tree binding documentation for serial flash with
Mediatek serial flash controller

Signed-off-by: Bayi Cheng <bayi.cheng@mediatek.com>
---
 Documentation/devicetree/bindings/mtd/mtk_nor.txt | 25 +++++++++++++++++++++++
 1 file changed, 25 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mtd/mtk_nor.txt

diff --git a/Documentation/devicetree/bindings/mtd/mtk_nor.txt b/Documentation/devicetree/bindings/mtd/mtk_nor.txt
new file mode 100644
index 0000000..0eca0cd
--- /dev/null
+++ b/Documentation/devicetree/bindings/mtd/mtk_nor.txt
@@ -0,0 +1,25 @@
+* MTD SPI nor driver for MTK MT81xx (and similar) serial flash controller
+
+MTK MT81xx serial flash controller is designed for serial Flash device.
+It supports one Flash device with signal mode, dual mode and quad mode.
+
+Required properties:
+- compatible: should be "mediatek,mt8173-nor";
+- reg: physical base address and length of the controller's register
+- clocks: spi nor source clock
+- clock-names: "spi_clk", "axi_clk", "mux_clk", "sf_clk"
+
+See Documentation/devicetree/bindings/clock/clock-bindings.txt
+and Documentation/mtd/spi-nor.txt for details.
+
+Example:
+nor_flash: nor at 1100d000 {
+	compatible = "mediatek,mt8173-nor";
+	reg = <0 0x1100d000 0 0xe0>;
+	clocks = <&pericfg CLK_PERI_SPI>,
+		 <&topckgen CLK_TOP_AXI_SEL>,
+		 <&topckgen CLK_TOP_UNIVPLL2_D8>,
+		 <&topckgen CLK_TOP_SPINFI_IFR_SEL>;
+	clock-names = "spi_clk", "axi_clk", "mux_clk", "sf_clk";
+};
+
-- 
1.8.1.1.dirty

[PATCH 1/3] doc: dt: add documentation for Mediatek spi-nor controller

[Jagan Teki]

On 8 September 2015 at 15:19, Bayi Cheng <bayi.cheng@mediatek.com> wrote:
> Add device tree binding documentation for serial flash with
> Mediatek serial flash controller
>
> Signed-off-by: Bayi Cheng <bayi.cheng@mediatek.com>
> ---
>  Documentation/devicetree/bindings/mtd/mtk_nor.txt | 25 +++++++++++++++++++++++
>  1 file changed, 25 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/mtd/mtk_nor.txt
>
> diff --git a/Documentation/devicetree/bindings/mtd/mtk_nor.txt b/Documentation/devicetree/bindings/mtd/mtk_nor.txt
> new file mode 100644
> index 0000000..0eca0cd
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mtd/mtk_nor.txt

IMHO - looks like the name of the driver file not resembles controller
driver, usually spi-nor framework has a name include 'nor' and related
controller drivers uses simple notion with vendor/soc_name-quadspi or
something similar.

cadence-quadspi.c
fsl-quadspi.c

Simple suggestion - mtk-quadspi.c (since it supports quad)

> @@ -0,0 +1,25 @@
> +* MTD SPI nor driver for MTK MT81xx (and similar) serial flash controller
> +
> +MTK MT81xx serial flash controller is designed for serial Flash device.
> +It supports one Flash device with signal mode, dual mode and quad mode.
> +
> +Required properties:
> +- compatible: should be "mediatek,mt8173-nor";
> +- reg: physical base address and length of the controller's register
> +- clocks: spi nor source clock
> +- clock-names: "spi_clk", "axi_clk", "mux_clk", "sf_clk"
> +
> +See Documentation/devicetree/bindings/clock/clock-bindings.txt

As this related to clock-names, just add this line in-continuous with
clock-name property description.

> +and Documentation/mtd/spi-nor.txt for details.

This explicit mentioning about spi-nor documentation is may not
required as this .txt will describe how spi-nor works and not related
to bindings.

> +
> +Example:
> +nor_flash: nor at 1100d000 {
> +       compatible = "mediatek,mt8173-nor";
> +       reg = <0 0x1100d000 0 0xe0>;
> +       clocks = <&pericfg CLK_PERI_SPI>,
> +                <&topckgen CLK_TOP_AXI_SEL>,
> +                <&topckgen CLK_TOP_UNIVPLL2_D8>,
> +                <&topckgen CLK_TOP_SPINFI_IFR_SEL>;
> +       clock-names = "spi_clk", "axi_clk", "mux_clk", "sf_clk";
> +};
> +
> --
> 1.8.1.1.dirty
>

thanks!
-- 
Jagan | openedev.

[PATCH 1/3] doc: dt: add documentation for Mediatek spi-nor controller

[bayi.cheng]

On Tue, 2015-09-08 at 17:04 +0530, Jagan Teki wrote:
> On 8 September 2015 at 15:19, Bayi Cheng <bayi.cheng@mediatek.com> wrote:
> > Add device tree binding documentation for serial flash with
> > Mediatek serial flash controller
> >
> > Signed-off-by: Bayi Cheng <bayi.cheng@mediatek.com>
> > ---
> >  Documentation/devicetree/bindings/mtd/mtk_nor.txt | 25 +++++++++++++++++++++++
> >  1 file changed, 25 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/mtd/mtk_nor.txt
> >
> > diff --git a/Documentation/devicetree/bindings/mtd/mtk_nor.txt b/Documentation/devicetree/bindings/mtd/mtk_nor.txt
> > new file mode 100644
> > index 0000000..0eca0cd
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/mtd/mtk_nor.txt
> 
> IMHO - looks like the name of the driver file not resembles controller
> driver, usually spi-nor framework has a name include 'nor' and related
> controller drivers uses simple notion with vendor/soc_name-quadspi or
> something similar.
> 
> cadence-quadspi.c
> fsl-quadspi.c
> 
> Simple suggestion - mtk-quadspi.c (since it supports quad)

Ok, Thanks for your instruct! I will change the name of the driver file
from mtk_nor.c to mtk-quadspi.c . at the same time, change the
mtk_nor.txt to mtk-quadspi.txt .
> 
> > @@ -0,0 +1,25 @@
> > +* MTD SPI nor driver for MTK MT81xx (and similar) serial flash controller
> > +
> > +MTK MT81xx serial flash controller is designed for serial Flash device.
> > +It supports one Flash device with signal mode, dual mode and quad mode.
> > +
> > +Required properties:
> > +- compatible: should be "mediatek,mt8173-nor";
> > +- reg: physical base address and length of the controller's register
> > +- clocks: spi nor source clock
> > +- clock-names: "spi_clk", "axi_clk", "mux_clk", "sf_clk"
> > +
> > +See Documentation/devicetree/bindings/clock/clock-bindings.txt
> 
> As this related to clock-names, just add this line in-continuous with
> clock-name property description.
> 
OK, I will change it.
> > +and Documentation/mtd/spi-nor.txt for details.
> 
> This explicit mentioning about spi-nor documentation is may not
> required as this .txt will describe how spi-nor works and not related
> to bindings.
> 
yes, you are right, and I will drop this line
> > +
> > +Example:
> > +nor_flash: nor at 1100d000 {
> > +       compatible = "mediatek,mt8173-nor";
> > +       reg = <0 0x1100d000 0 0xe0>;
> > +       clocks = <&pericfg CLK_PERI_SPI>,
> > +                <&topckgen CLK_TOP_AXI_SEL>,
> > +                <&topckgen CLK_TOP_UNIVPLL2_D8>,
> > +                <&topckgen CLK_TOP_SPINFI_IFR_SEL>;
> > +       clock-names = "spi_clk", "axi_clk", "mux_clk", "sf_clk";
> > +};
> > +
> > --
> > 1.8.1.1.dirty
> >
> 
> thanks!

[PATCH 1/3] doc: dt: add documentation for Mediatek spi-nor controller

[Sascha Hauer]

On Tue, Sep 08, 2015 at 05:49:54PM +0800, Bayi Cheng wrote:
> Add device tree binding documentation for serial flash with
> Mediatek serial flash controller
> 
> Signed-off-by: Bayi Cheng <bayi.cheng@mediatek.com>
> ---
>  Documentation/devicetree/bindings/mtd/mtk_nor.txt | 25 +++++++++++++++++++++++
>  1 file changed, 25 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/mtd/mtk_nor.txt
> 
> diff --git a/Documentation/devicetree/bindings/mtd/mtk_nor.txt b/Documentation/devicetree/bindings/mtd/mtk_nor.txt
> new file mode 100644
> index 0000000..0eca0cd
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mtd/mtk_nor.txt
> @@ -0,0 +1,25 @@
> +* MTD SPI nor driver for MTK MT81xx (and similar) serial flash controller
> +
> +MTK MT81xx serial flash controller is designed for serial Flash device.
> +It supports one Flash device with signal mode, dual mode and quad mode.
> +
> +Required properties:
> +- compatible: should be "mediatek,mt8173-nor";
> +- reg: physical base address and length of the controller's register
> +- clocks: spi nor source clock
> +- clock-names: "spi_clk", "axi_clk", "mux_clk", "sf_clk"

Drop the _clk suffix. It's the clock-names property which already makes
it clear that these are clock names.

Sascha


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[PATCH 1/3] doc: dt: add documentation for Mediatek spi-nor controller

[bayi.cheng]

On Wed, 2015-09-09 at 07:47 +0200, Sascha Hauer wrote:
> On Tue, Sep 08, 2015 at 05:49:54PM +0800, Bayi Cheng wrote:
> > Add device tree binding documentation for serial flash with
> > Mediatek serial flash controller
> > 
> > Signed-off-by: Bayi Cheng <bayi.cheng@mediatek.com>
> > ---
> >  Documentation/devicetree/bindings/mtd/mtk_nor.txt | 25 +++++++++++++++++++++++
> >  1 file changed, 25 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/mtd/mtk_nor.txt
> > 
> > diff --git a/Documentation/devicetree/bindings/mtd/mtk_nor.txt b/Documentation/devicetree/bindings/mtd/mtk_nor.txt
> > new file mode 100644
> > index 0000000..0eca0cd
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/mtd/mtk_nor.txt
> > @@ -0,0 +1,25 @@
> > +* MTD SPI nor driver for MTK MT81xx (and similar) serial flash controller
> > +
> > +MTK MT81xx serial flash controller is designed for serial Flash device.
> > +It supports one Flash device with signal mode, dual mode and quad mode.
> > +
> > +Required properties:
> > +- compatible: should be "mediatek,mt8173-nor";
> > +- reg: physical base address and length of the controller's register
> > +- clocks: spi nor source clock
> > +- clock-names: "spi_clk", "axi_clk", "mux_clk", "sf_clk"
> 
> Drop the _clk suffix. It's the clock-names property which already makes
> it clear that these are clock names.
> 
> Sascha
> 
> 
OK, I will drop the _clk suffix here!

[PATCH 1/3] doc: dt: add documentation for Mediatek spi-nor controller

[Brian Norris]

On Tue, Sep 08, 2015 at 05:49:54PM +0800, Bayi Cheng wrote:
> Add device tree binding documentation for serial flash with
> Mediatek serial flash controller
> 
> Signed-off-by: Bayi Cheng <bayi.cheng@mediatek.com>
> ---
>  Documentation/devicetree/bindings/mtd/mtk_nor.txt | 25 +++++++++++++++++++++++
>  1 file changed, 25 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/mtd/mtk_nor.txt
> 
> diff --git a/Documentation/devicetree/bindings/mtd/mtk_nor.txt b/Documentation/devicetree/bindings/mtd/mtk_nor.txt
> new file mode 100644
> index 0000000..0eca0cd
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mtd/mtk_nor.txt
> @@ -0,0 +1,25 @@
> +* MTD SPI nor driver for MTK MT81xx (and similar) serial flash controller
> +
> +MTK MT81xx serial flash controller is designed for serial Flash device.
> +It supports one Flash device with signal mode, dual mode and quad mode.
> +
> +Required properties:
> +- compatible: should be "mediatek,mt8173-nor";
> +- reg: physical base address and length of the controller's register
> +- clocks: spi nor source clock
> +- clock-names: "spi_clk", "axi_clk", "mux_clk", "sf_clk"
> +
> +See Documentation/devicetree/bindings/clock/clock-bindings.txt
> +and Documentation/mtd/spi-nor.txt for details.
> +
> +Example:
> +nor_flash: nor at 1100d000 {
> +	compatible = "mediatek,mt8173-nor";
> +	reg = <0 0x1100d000 0 0xe0>;
> +	clocks = <&pericfg CLK_PERI_SPI>,
> +		 <&topckgen CLK_TOP_AXI_SEL>,
> +		 <&topckgen CLK_TOP_UNIVPLL2_D8>,
> +		 <&topckgen CLK_TOP_SPINFI_IFR_SEL>;
> +	clock-names = "spi_clk", "axi_clk", "mux_clk", "sf_clk";
> +};

I understand that for now, you only support a single flash, and you
don't need any extra flash-specific DT properties, but in the interest
of being more generic and more in-line with other drivers, can you
include:

  * #addres-cells (= <1>) and #size-cells (= <0>) properties
  * sub-node(s) representing the flash; reference [1], and there's a
    good example in a recent submission [2]

So I'd expect something like:

	nor_flash: nor at 1100d000 {
		compatible = "mediatek,mt8173-nor";
		...
		#address-cells = <1>;
		#size-cells = <0>;

		flash at 0 {
			compatible = "jedec,spi-nor";
			reg = <0>;
			...
		};
	};

This patch is also relevant [3] (hopefully I'll get to merge that one
soon); you'll want to use the sub-node (not the main node) when
initializing the flash device.

I think maybe we'll want to codify some of this in a "SPI NOR
controller" document, so we can make sure more developers follow this
when designing their binding.

Brian

[1] https://www.kernel.org/doc/Documentation/devicetree/bindings/mtd/jedec,spi-nor.txt
[2] http://lists.infradead.org/pipermail/linux-mtd/2015-August/061439.html
[3] http://lists.infradead.org/pipermail/linux-mtd/2015-September/061637.html

[PATCH 1/3] doc: dt: add documentation for Mediatek spi-nor controller

[Brian Norris]

One more thing:

On Tue, Sep 08, 2015 at 05:49:54PM +0800, Bayi Cheng wrote:
> +- clocks: spi nor source clock

^^ you only list one clock here

> +- clock-names: "spi_clk", "axi_clk", "mux_clk", "sf_clk"

But you have 4 names here.

...
> +	clocks = <&pericfg CLK_PERI_SPI>,
> +		 <&topckgen CLK_TOP_AXI_SEL>,
> +		 <&topckgen CLK_TOP_UNIVPLL2_D8>,
> +		 <&topckgen CLK_TOP_SPINFI_IFR_SEL>;

And you provide 4 clocks.

> +	clock-names = "spi_clk", "axi_clk", "mux_clk", "sf_clk";

Please list all 4 under the "clocks" property, not just under the
"clock-names" property.

Brian

[PATCH 1/3] doc: dt: add documentation for Mediatek spi-nor controller

[bayi.cheng]

On Fri, 2015-09-11 at 14:49 -0700, Brian Norris wrote:
> One more thing:
> 
> On Tue, Sep 08, 2015 at 05:49:54PM +0800, Bayi Cheng wrote:
> > +- clocks: spi nor source clock
> 
> ^^ you only list one clock here
> 
Ok, I will add other clocks
> > +- clock-names: "spi_clk", "axi_clk", "mux_clk", "sf_clk"
> 
> But you have 4 names here.
> 
> ...
> > +	clocks = <&pericfg CLK_PERI_SPI>,
> > +		 <&topckgen CLK_TOP_AXI_SEL>,
> > +		 <&topckgen CLK_TOP_UNIVPLL2_D8>,
> > +		 <&topckgen CLK_TOP_SPINFI_IFR_SEL>;
> 
> And you provide 4 clocks.
> 
> > +	clock-names = "spi_clk", "axi_clk", "mux_clk", "sf_clk";
> 
> Please list all 4 under the "clocks" property, not just under the
> "clock-names" property.
> 
OK,  Thanks for your remind!
> Brian

[PATCH 2/3] mtd: mtk-nor: mtk serial flash controller driver

[Bayi Cheng]

add spi nor flash driver for mediatek controller

Signed-off-by: Bayi Cheng <bayi.cheng@mediatek.com>
---
 drivers/mtd/spi-nor/Kconfig   |   7 +
 drivers/mtd/spi-nor/Makefile  |   1 +
 drivers/mtd/spi-nor/mtk_nor.c | 533 ++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 541 insertions(+)
 create mode 100644 drivers/mtd/spi-nor/mtk_nor.c

diff --git a/drivers/mtd/spi-nor/Kconfig b/drivers/mtd/spi-nor/Kconfig
index 89bf4c1..f433890 100644
--- a/drivers/mtd/spi-nor/Kconfig
+++ b/drivers/mtd/spi-nor/Kconfig
@@ -7,6 +7,13 @@ menuconfig MTD_SPI_NOR
 
 if MTD_SPI_NOR
 
+config MTD_MT81xx_NOR
+	tristate "Support SPI flash Controller MTD_MT81xx_NOR"
+	help
+	  This enables access to SPI Nor flash, using MTD_MT81XX_NOR controller.
+	  This controller does nor support generic SPI BUS, It only supports
+	  SPI NOR Flash.
+
 config MTD_SPI_NOR_USE_4K_SECTORS
 	bool "Use small 4096 B erase sectors"
 	default y
diff --git a/drivers/mtd/spi-nor/Makefile b/drivers/mtd/spi-nor/Makefile
index e53333e..2f4fe62 100644
--- a/drivers/mtd/spi-nor/Makefile
+++ b/drivers/mtd/spi-nor/Makefile
@@ -1,3 +1,4 @@
+obj-$(CONFIG_MTD_MT81xx_NOR)	+= mtk_nor.o
 obj-$(CONFIG_MTD_SPI_NOR)	+= spi-nor.o
 obj-$(CONFIG_SPI_FSL_QUADSPI)	+= fsl-quadspi.o
 obj-$(CONFIG_SPI_NXP_SPIFI)	+= nxp-spifi.o
diff --git a/drivers/mtd/spi-nor/mtk_nor.c b/drivers/mtd/spi-nor/mtk_nor.c
new file mode 100644
index 0000000..e675fb6
--- /dev/null
+++ b/drivers/mtd/spi-nor/mtk_nor.c
@@ -0,0 +1,533 @@
+/*
+ * Copyright (c) 2015 MediaTek Inc.
+ * Author: Bayi.Cheng <bayi.cheng@mediatek.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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/ioport.h>
+#include <linux/math64.h>
+#include <linux/module.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_gpio.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
+#include <linux/mtd/spi-nor.h>
+
+#define MTK_NOR_CMD_REG			0x00
+#define MTK_NOR_CNT_REG			0x04
+#define MTK_NOR_RDSR_REG		0x08
+#define MTK_NOR_RDATA_REG		0x0c
+#define MTK_NOR_RADR0_REG		0x10
+#define MTK_NOR_RADR1_REG		0x14
+#define MTK_NOR_RADR2_REG		0x18
+#define MTK_NOR_WDATA_REG		0x1c
+#define MTK_NOR_PRGDATA0_REG		0x20
+#define MTK_NOR_PRGDATA1_REG		0x24
+#define MTK_NOR_PRGDATA2_REG		0x28
+#define MTK_NOR_PRGDATA3_REG		0x2c
+#define MTK_NOR_PRGDATA4_REG		0x30
+#define MTK_NOR_PRGDATA5_REG		0x34
+#define MTK_NOR_SHREG0_REG		0x38
+#define MTK_NOR_SHREG1_REG		0x3c
+#define MTK_NOR_SHREG2_REG		0x40
+#define MTK_NOR_SHREG3_REG		0x44
+#define MTK_NOR_SHREG4_REG		0x48
+#define MTK_NOR_SHREG5_REG		0x4c
+#define MTK_NOR_SHREG6_REG		0x50
+#define MTK_NOR_SHREG7_REG		0x54
+#define MTK_NOR_SHREG8_REG		0x58
+#define MTK_NOR_SHREG9_REG		0x5c
+#define MTK_NOR_FLHCFG_REG		0x84
+#define MTK_NOR_PP_DATA_REG		0x98
+#define MTK_NOR_PREBUF_STUS_REG		0x9c
+#define MTK_NOR_INTRSTUS_REG		0xa8
+#define MTK_NOR_INTREN_REG		0xac
+#define MTK_NOR_TIME_REG		0x94
+#define MTK_NOR_CHKSUM_CTL_REG		0xb8
+#define MTK_NOR_CHKSUM_REG		0xbc
+#define MTK_NOR_CMD2_REG		0xc0
+#define MTK_NOR_WRPROT_REG		0xc4
+#define MTK_NOR_RADR3_REG		0xc8
+#define MTK_NOR_DUAL_REG		0xcc
+#define MTK_NOR_DELSEL0_REG		0xa0
+#define MTK_NOR_DELSEL1_REG		0xa4
+#define MTK_NOR_DELSEL2_REG		0xd0
+#define MTK_NOR_DELSEL3_REG		0xd4
+#define MTK_NOR_DELSEL4_REG		0xd8
+#define MTK_NOR_CFG1_REG		0x60
+#define MTK_NOR_CFG2_REG		0x64
+#define MTK_NOR_CFG3_REG		0x68
+#define MTK_NOR_STATUS0_REG		0x70
+#define MTK_NOR_STATUS1_REG		0x74
+#define MTK_NOR_STATUS2_REG		0x78
+#define MTK_NOR_STATUS3_REG		0x7c
+/* commands for mtk nor controller */
+#define MTK_NOR_READ_CMD		0x0
+#define MTK_NOR_RDSR_CMD		0x2
+#define MTK_NOR_PRG_CMD			0x4
+#define MTK_NOR_WR_CMD			0x10
+#define MTK_NOR_WRSR_CMD		0x20
+#define MTK_NOR_PIO_READ_CMD		0x81
+#define MTK_NOR_WR_BUF_ENABLE		0x1
+#define MTK_NOR_WR_BUF_DISABLE		0x0
+#define MTK_NOR_ENABLE_SF_CMD		0x30
+#define MTK_NOR_DUAD_ADDR_EN		0x8
+#define MTK_NOR_QUAD_READ_EN		0x4
+#define MTK_NOR_DUAL_ADDR_EN		0x2
+#define MTK_NOR_DUAL_READ_EN		0x1
+#define MTK_NOR_DUAL_DISABLE		0x0
+#define MTK_NOR_FAST_READ		0x1
+
+#define SFLASH_WRBUF_SIZE		128
+#define MAX_FLASHCOUNT			1
+#define SFLASHHWNAME_LEN		12
+#define SFLASH_MAX_DMA_SIZE		(1024 * 8)
+
+#define LoWord(d)		((u16)(d & 0x0000ffffL))
+#define HiWord(d)		((u16)((d >> 16) & 0x0000ffffL))
+#define LoByte(w)		((u8)(w & 0x00ff))
+#define HiByte(w)		((u8)(((w) >> 8) & 0x00ff))
+#define LOCAL_BUF_SIZE		(SFLASH_MAX_DMA_SIZE * 20)
+
+struct mt8173_nor {
+	struct mtd_info mtd;
+	struct spi_nor nor;
+	struct device *dev;
+	void __iomem *base;	/* nor flash base address */
+	struct clk *spi_clk;
+	struct clk *src_axi_clk;
+	struct clk *sf_mux_clk;
+	struct clk *nor_clk;
+};
+
+static void mt8173_nor_set_read_mode(struct mt8173_nor *mt8173_nor)
+{
+	struct spi_nor *nor = &mt8173_nor->nor;
+
+	switch (nor->flash_read) {
+	case SPI_NOR_FAST:
+		writeb(SPINOR_OP_READ_FAST, mt8173_nor->base +
+		       MTK_NOR_PRGDATA3_REG);
+		writeb(MTK_NOR_FAST_READ, mt8173_nor->base +
+		       MTK_NOR_CFG1_REG);
+		break;
+	case SPI_NOR_DUAL:
+		writeb(SPINOR_OP_READ_1_1_2, mt8173_nor->base +
+		       MTK_NOR_PRGDATA3_REG);
+		writeb(MTK_NOR_DUAL_READ_EN, mt8173_nor->base +
+		       MTK_NOR_DUAL_REG);
+		break;
+	case SPI_NOR_QUAD:
+		writeb(SPINOR_OP_READ_1_1_4, mt8173_nor->base +
+		       MTK_NOR_PRGDATA3_REG);
+		writeb(MTK_NOR_QUAD_READ_EN, mt8173_nor->base +
+		       MTK_NOR_DUAL_REG);
+		break;
+	default:
+		writeb(SPINOR_OP_READ, mt8173_nor->base +
+		       MTK_NOR_PRGDATA3_REG);
+		writeb(MTK_NOR_DUAL_DISABLE, mt8173_nor->base +
+		       MTK_NOR_DUAL_REG);
+		break;
+	}
+}
+
+static int mt8173_nor_polling_reg(struct mt8173_nor *mt8173_nor, int compare)
+{
+	int reg, ret;
+
+	ret =  readl_poll_timeout(mt8173_nor->base + MTK_NOR_CMD_REG, reg,
+				  !(reg & compare), 100, 10000);
+	if (ret)
+		dev_err(mt8173_nor->dev, "compare val%02X timeout!\n", compare);
+	return ret;
+}
+
+static int mt8173_nor_execute_cmd(struct mt8173_nor *mt8173_nor, u8 cmdval)
+{
+	u8 val = cmdval & 0x1f;
+
+	writeb(cmdval, mt8173_nor->base + MTK_NOR_CMD_REG);
+	return mt8173_nor_polling_reg(mt8173_nor, val);
+}
+
+static int mt8173_nor_set_cmd(struct mt8173_nor *mt8173_nor, int addr,
+			      int len, int op)
+{
+	writeb(op, mt8173_nor->base + MTK_NOR_PRGDATA5_REG);
+	/* reset the following register */
+	writeb(LoByte(HiWord(addr)), mt8173_nor->base + MTK_NOR_PRGDATA4_REG);
+	writeb(HiByte(LoWord(addr)), mt8173_nor->base + MTK_NOR_PRGDATA3_REG);
+	writeb(LoByte(LoWord(addr)), mt8173_nor->base + MTK_NOR_PRGDATA2_REG);
+	writeb(len, mt8173_nor->base + MTK_NOR_CNT_REG);
+	return mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_PRG_CMD);
+}
+
+static int mt8173_nor_get_para(struct mt8173_nor *mt8173_nor, u8 *buf, int len)
+{
+	if (len > 1) {
+		/* read JEDEC ID need 4 bytes commands */
+		mt8173_nor_set_cmd(mt8173_nor, 0, 32, SPINOR_OP_RDID);
+		buf[2] = readb(mt8173_nor->base + MTK_NOR_SHREG0_REG);
+		buf[1] = readb(mt8173_nor->base + MTK_NOR_SHREG1_REG);
+		buf[0] = readb(mt8173_nor->base + MTK_NOR_SHREG2_REG);
+	} else {
+		if (mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_RDSR_CMD)) {
+			dev_err(mt8173_nor->dev, "read status failed!\n");
+			return -EINVAL;
+		}
+		*buf = readb(mt8173_nor->base + MTK_NOR_RDSR_REG);
+	}
+	return 0;
+}
+
+/* cmd1 sent to nor flash, cmd2 write to nor controller */
+static int mt8173_nor_set_para(struct mt8173_nor *mt8173_nor, int cmd1,
+			       int cmd2)
+{
+	if (mt8173_nor_set_cmd(mt8173_nor, 0, 8, SPINOR_OP_WREN)) {
+		dev_err(mt8173_nor->dev,
+			"write enable failed in write protect!\n");
+		return -EINVAL;
+	}
+	writeb(cmd1, mt8173_nor->base + MTK_NOR_PRGDATA5_REG);
+	writeb(8, mt8173_nor->base + MTK_NOR_CNT_REG);
+	if (mt8173_nor_execute_cmd(mt8173_nor, cmd2)) {
+		dev_err(mt8173_nor->dev, "execute cmd failed!\n");
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static int mt8173_nor_write_buffer_enable(struct mt8173_nor *mt8173_nor)
+{
+	u8 reg, ret;
+
+	writel(MTK_NOR_WR_BUF_ENABLE, mt8173_nor->base + MTK_NOR_CFG2_REG);
+	ret =  readb_poll_timeout(mt8173_nor->base + MTK_NOR_CFG2_REG, reg,
+				  0x01 == (reg & 0x01), 100, 10000);
+	if (ret)
+		dev_err(mt8173_nor->dev, "timeout!\n");
+	return ret;
+}
+
+static int mt8173_nor_write_buffer_disable(struct mt8173_nor *mt8173_nor)
+{
+	u8 reg, ret;
+
+	writel(MTK_NOR_WR_BUF_DISABLE, mt8173_nor->base + MTK_NOR_CFG2_REG);
+	ret =  readb_poll_timeout(mt8173_nor->base + MTK_NOR_CFG2_REG, reg,
+				  MTK_NOR_WR_BUF_DISABLE == (reg & 0xf), 100,
+				  10000);
+	if (ret)
+		dev_err(mt8173_nor->dev, "compare timeout!\n");
+	return ret;
+}
+
+static int mt8173_nor_erase_sector(struct spi_nor *nor, loff_t offset)
+{
+	struct mt8173_nor *mt8173_nor = nor->priv;
+
+	if (mt8173_nor_set_cmd(mt8173_nor, 0, 8, SPINOR_OP_WREN)) {
+		dev_err(mt8173_nor->dev,
+			"write enable failed in erase sector!\n");
+		return -EINVAL;
+	}
+
+	mt8173_nor_set_cmd(mt8173_nor, (int)offset, 32, SPINOR_OP_BE_4K);
+	return 0;
+}
+
+static int mt8173_nor_read_hw(struct mt8173_nor *mt8173_nor, int addr, int len,
+			      int *retlen, u8 *buf)
+{
+	int ret = 0, i;
+
+	mt8173_nor_set_read_mode(mt8173_nor);
+	writeb(HiByte(HiWord(addr)), mt8173_nor->base + MTK_NOR_RADR3_REG);
+	writeb(LoByte(HiWord(addr)), mt8173_nor->base + MTK_NOR_RADR2_REG);
+	writeb(HiByte(LoWord(addr)), mt8173_nor->base + MTK_NOR_RADR1_REG);
+	writeb(LoByte(LoWord(addr)), mt8173_nor->base + MTK_NOR_RADR0_REG);
+
+	for (i = 0; i < len; i++, (*retlen)++) {
+		if (mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_PIO_READ_CMD)) {
+			dev_err(mt8173_nor->dev, "read flash failed!\n");
+			return -EINVAL;
+		}
+		buf[i] = readb(mt8173_nor->base + MTK_NOR_RDATA_REG);
+	}
+	return ret;
+}
+
+static int mt8173_nor_read(struct spi_nor *nor, loff_t from, size_t len,
+			   size_t *retlen, u_char *buf)
+{
+	struct mt8173_nor *mt8173_nor = nor->priv;
+
+	return mt8173_nor_read_hw(mt8173_nor, (int)from, (int)len,
+				 (int *)retlen, (u8 *)buf);
+}
+
+static int mt8173_nor_write_single_byte(struct mt8173_nor *mt8173_nor,
+					int u4addr, u8 u1data)
+{
+	if (u4addr >= mt8173_nor->mtd.size) {
+		dev_err(mt8173_nor->dev, "invalid write address!\n");
+		return -EINVAL;
+	}
+
+	writeb(u1data, mt8173_nor->base + MTK_NOR_WDATA_REG);
+	writeb(LoByte(HiWord(u4addr)), mt8173_nor->base + MTK_NOR_RADR2_REG);
+	writeb(HiByte(LoWord(u4addr)), mt8173_nor->base + MTK_NOR_RADR1_REG);
+	writeb(LoByte(LoWord(u4addr)), mt8173_nor->base + MTK_NOR_RADR0_REG);
+
+	if (mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_WR_CMD)) {
+		dev_err(mt8173_nor->dev, "write byte offset%08x\n", u4addr);
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static int mt8173_nor_write_buffer(struct mt8173_nor *mt8173_nor, int u4addr,
+				   int u4len, const u8 *buf)
+{
+	int i, j, bufidx, data;
+
+	if (!buf)
+		return -EINVAL;
+
+	writeb(LoByte(HiWord(u4addr)), mt8173_nor->base + MTK_NOR_RADR2_REG);
+	writeb(HiByte(LoWord(u4addr)), mt8173_nor->base + MTK_NOR_RADR1_REG);
+	writeb(LoByte(LoWord(u4addr)), mt8173_nor->base + MTK_NOR_RADR0_REG);
+
+	bufidx = 0;
+	for (i = 0; i < u4len; i += 4) {
+		for (j = 0; j < 4; j++) {
+			(*((u8 *)&data + j)) = buf[bufidx];
+			bufidx++;
+		}
+		writel(data, mt8173_nor->base + MTK_NOR_PP_DATA_REG);
+	}
+
+	if (mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_WR_CMD)) {
+		dev_err(mt8173_nor->dev, "write buffer offset:%08x\n", u4addr);
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static void mt8173_nor_write(struct spi_nor *nor, loff_t to, size_t len,
+			     size_t *retlen, const u_char *buf)
+{
+	struct mt8173_nor *mt8173_nor = nor->priv;
+	size_t i;
+
+	if (nor->page_size == len) {
+		if (mt8173_nor_write_buffer_enable(mt8173_nor))
+			dev_err(mt8173_nor->dev, "write buffer enable failed !\n");
+		while (len > 0) {
+			mt8173_nor_write_buffer(mt8173_nor, to,
+						SFLASH_WRBUF_SIZE, buf);
+			len -= SFLASH_WRBUF_SIZE;
+			to += SFLASH_WRBUF_SIZE;
+			buf += SFLASH_WRBUF_SIZE;
+			(*retlen) += SFLASH_WRBUF_SIZE;
+		}
+		if (mt8173_nor_write_buffer_disable(mt8173_nor))
+			dev_err(mt8173_nor->dev, "write buffer disable failed !\n");
+	} else {
+		for (i = 0; i < len; i++,  (*retlen)++) {
+			if (mt8173_nor_write_single_byte(mt8173_nor, to, *buf))
+				dev_err(mt8173_nor->dev, "write byte failed !\n");
+			to++;
+			buf++;
+		}
+	}
+}
+
+static int mt8173_nor_read_reg(struct spi_nor *nor, u8 opcode, u8 *buf, int len)
+{
+	int ret = 0;
+	struct mt8173_nor *mt8173_nor = nor->priv;
+	/* mtk nor controller haven't supoort SPINOR_OP_RDCR */
+	if (opcode == SPINOR_OP_RDID || opcode == SPINOR_OP_RDSR)
+		ret = mt8173_nor_get_para(mt8173_nor, buf, len);
+	else
+		dev_warn(mt8173_nor->dev, "invalid cmd %d\n", opcode);
+
+	return ret;
+}
+
+static int mt8173_nor_write_reg(struct spi_nor *nor, u8 opcode, u8 *buf,
+				int len, int write_enable)
+{
+	int ret, cmd_to_nor, cmd_to_controller;
+	struct mt8173_nor *mt8173_nor = nor->priv;
+
+	if (opcode == SPINOR_OP_WRSR || opcode == SPINOR_OP_CHIP_ERASE) {
+		if (len > 0) {
+			cmd_to_nor = *buf;
+			cmd_to_controller = MTK_NOR_WRSR_CMD;
+		} else {
+			cmd_to_nor = opcode;
+			cmd_to_controller = MTK_NOR_PRG_CMD;
+		}
+		ret = mt8173_nor_set_para(mt8173_nor, cmd_to_nor,
+					  cmd_to_controller);
+	} else if (opcode == SPINOR_OP_WREN || opcode == SPINOR_OP_WRDI) {
+		ret = mt8173_nor_set_cmd(mt8173_nor, 0, 8, opcode);
+	} else {
+		dev_warn(mt8173_nor->dev, "have not support cmd %d\n", opcode);
+		ret = -EINVAL;
+	}
+	return ret;
+}
+
+static int __init mtk_nor_init(struct mt8173_nor *mt8173_nor,
+			       struct mtd_part_parser_data ppdata)
+{
+	int ret;
+	struct spi_nor *nor;
+	struct mtd_info *mtd;
+
+	writel(MTK_NOR_ENABLE_SF_CMD, mt8173_nor->base + MTK_NOR_WRPROT_REG);
+	nor = &mt8173_nor->nor;
+	mtd = &mt8173_nor->mtd;
+	nor->mtd = mt8173_nor->mtd;
+	nor->dev = mt8173_nor->dev;
+	nor->priv = mt8173_nor;
+	mtd->priv = nor;
+
+	/* fill the hooks to spi nor */
+	nor->read = mt8173_nor_read;
+	nor->read_reg = mt8173_nor_read_reg;
+	nor->write = mt8173_nor_write;
+	nor->write_reg = mt8173_nor_write_reg;
+	nor->erase = mt8173_nor_erase_sector;
+	nor->mtd.owner = THIS_MODULE;
+	nor->mtd.name = "mtk_nor";
+	/* initialized with NULL */
+	ret = spi_nor_scan(nor, NULL, SPI_NOR_DUAL);
+	if (ret) {
+		dev_err(mt8173_nor->dev, "spi_nor_scan failed !\n");
+		return -EINVAL;
+	}
+	dev_dbg(mt8173_nor->dev, "mtd->size :0x%llx!\n", mtd->size);
+	ret = mtd_device_parse_register(&nor->mtd, NULL, &ppdata, NULL, 0);
+
+	return ret;
+}
+
+static int mtk_nor_drv_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct mtd_part_parser_data ppdata;
+	struct resource *res;
+	int ret;
+	struct mt8173_nor *mt8173_nor = devm_kzalloc(&pdev->dev,
+		sizeof(*mt8173_nor), GFP_KERNEL);
+
+	if (!pdev->dev.of_node) {
+		dev_err(&pdev->dev, "No DT found\n");
+		return -EINVAL;
+	}
+
+	if (!mt8173_nor)
+		return -ENOMEM;
+	platform_set_drvdata(pdev, mt8173_nor);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	mt8173_nor->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(mt8173_nor->base)) {
+		ret = PTR_ERR(mt8173_nor->base);
+		goto nor_free;
+	}
+
+	mt8173_nor->spi_clk = devm_clk_get(&pdev->dev, "spi_clk");
+	if (IS_ERR(mt8173_nor->spi_clk)) {
+		ret = PTR_ERR(mt8173_nor->spi_clk);
+		goto nor_free;
+	}
+
+	mt8173_nor->src_axi_clk = devm_clk_get(&pdev->dev, "axi_clk");
+	if (IS_ERR(mt8173_nor->src_axi_clk)) {
+		ret = PTR_ERR(mt8173_nor->src_axi_clk);
+		goto nor_free;
+	}
+
+	mt8173_nor->sf_mux_clk = devm_clk_get(&pdev->dev, "mux_clk");
+	if (IS_ERR(mt8173_nor->sf_mux_clk)) {
+		ret = PTR_ERR(mt8173_nor->sf_mux_clk);
+		goto nor_free;
+	}
+
+	mt8173_nor->nor_clk = devm_clk_get(&pdev->dev, "sf_clk");
+	if (IS_ERR(mt8173_nor->nor_clk)) {
+		ret = PTR_ERR(mt8173_nor->nor_clk);
+		goto nor_free;
+	}
+
+	mt8173_nor->dev = &pdev->dev;
+	clk_prepare_enable(mt8173_nor->spi_clk);
+	clk_prepare_enable(mt8173_nor->src_axi_clk);
+	clk_prepare_enable(mt8173_nor->sf_mux_clk);
+	clk_prepare_enable(mt8173_nor->nor_clk);
+	clk_set_parent(mt8173_nor->nor_clk, mt8173_nor->sf_mux_clk);
+
+	ppdata.of_node = np;
+	ret = mtk_nor_init(mt8173_nor, ppdata);
+
+nor_free:
+	return ret;
+}
+
+static int mtk_nor_drv_remove(struct platform_device *pdev)
+{
+	struct mt8173_nor *mt8173_nor = platform_get_drvdata(pdev);
+
+	clk_disable_unprepare(mt8173_nor->spi_clk);
+	clk_disable_unprepare(mt8173_nor->src_axi_clk);
+	clk_disable_unprepare(mt8173_nor->sf_mux_clk);
+	clk_disable_unprepare(mt8173_nor->nor_clk);
+	mtd_device_unregister(&mt8173_nor->mtd);
+	return 0;
+}
+
+static const struct of_device_id mtk_nor_of_ids[] = {
+	{ .compatible = "mediatek,mt8173-nor"},
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, mtk_nor_of_ids);
+
+static struct platform_driver mtk_nor_driver = {
+	.probe = mtk_nor_drv_probe,
+	.remove = mtk_nor_drv_remove,
+	.driver = {
+		.name = "mtk-nor",
+		.of_match_table = mtk_nor_of_ids,
+	},
+};
+
+module_platform_driver(mtk_nor_driver);
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("MediaTek SPI NOR Flash Driver");
-- 
1.8.1.1.dirty

[PATCH 2/3] mtd: mtk-nor: mtk serial flash controller driver

[Sascha Hauer]

On Tue, Sep 08, 2015 at 05:49:55PM +0800, Bayi Cheng wrote:
> add spi nor flash driver for mediatek controller
> 
> Signed-off-by: Bayi Cheng <bayi.cheng@mediatek.com>
> ---
>  drivers/mtd/spi-nor/Kconfig   |   7 +
>  drivers/mtd/spi-nor/Makefile  |   1 +
>  drivers/mtd/spi-nor/mtk_nor.c | 533 ++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 541 insertions(+)
>  create mode 100644 drivers/mtd/spi-nor/mtk_nor.c
> 
> diff --git a/drivers/mtd/spi-nor/Kconfig b/drivers/mtd/spi-nor/Kconfig
> index 89bf4c1..f433890 100644
> --- a/drivers/mtd/spi-nor/Kconfig
> +++ b/drivers/mtd/spi-nor/Kconfig
> @@ -7,6 +7,13 @@ menuconfig MTD_SPI_NOR
>  
>  if MTD_SPI_NOR
>  
> +config MTD_MT81xx_NOR
> +	tristate "Support SPI flash Controller MTD_MT81xx_NOR"
> +	help
> +	  This enables access to SPI Nor flash, using MTD_MT81XX_NOR controller.
> +	  This controller does nor support generic SPI BUS, It only supports
> +	  SPI NOR Flash.
> +
>  config MTD_SPI_NOR_USE_4K_SECTORS
>  	bool "Use small 4096 B erase sectors"
>  	default y
> diff --git a/drivers/mtd/spi-nor/Makefile b/drivers/mtd/spi-nor/Makefile
> index e53333e..2f4fe62 100644
> --- a/drivers/mtd/spi-nor/Makefile
> +++ b/drivers/mtd/spi-nor/Makefile
> @@ -1,3 +1,4 @@
> +obj-$(CONFIG_MTD_MT81xx_NOR)	+= mtk_nor.o
>  obj-$(CONFIG_MTD_SPI_NOR)	+= spi-nor.o
>  obj-$(CONFIG_SPI_FSL_QUADSPI)	+= fsl-quadspi.o
>  obj-$(CONFIG_SPI_NXP_SPIFI)	+= nxp-spifi.o
> diff --git a/drivers/mtd/spi-nor/mtk_nor.c b/drivers/mtd/spi-nor/mtk_nor.c
> new file mode 100644
> index 0000000..e675fb6
> --- /dev/null
> +++ b/drivers/mtd/spi-nor/mtk_nor.c
> @@ -0,0 +1,533 @@
> +/*
> + * Copyright (c) 2015 MediaTek Inc.
> + * Author: Bayi.Cheng <bayi.cheng@mediatek.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.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/device.h>
> +#include <linux/init.h>
> +#include <linux/io.h>
> +#include <linux/iopoll.h>
> +#include <linux/ioport.h>
> +#include <linux/math64.h>
> +#include <linux/module.h>
> +#include <linux/mtd/mtd.h>
> +#include <linux/mutex.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/of_gpio.h>
> +#include <linux/pinctrl/consumer.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +#include <linux/mtd/mtd.h>
> +#include <linux/mtd/partitions.h>
> +#include <linux/mtd/spi-nor.h>
> +
> +#define MTK_NOR_CMD_REG			0x00
> +#define MTK_NOR_CNT_REG			0x04
> +#define MTK_NOR_RDSR_REG		0x08
> +#define MTK_NOR_RDATA_REG		0x0c
> +#define MTK_NOR_RADR0_REG		0x10
> +#define MTK_NOR_RADR1_REG		0x14
> +#define MTK_NOR_RADR2_REG		0x18
> +#define MTK_NOR_WDATA_REG		0x1c
> +#define MTK_NOR_PRGDATA0_REG		0x20
> +#define MTK_NOR_PRGDATA1_REG		0x24
> +#define MTK_NOR_PRGDATA2_REG		0x28
> +#define MTK_NOR_PRGDATA3_REG		0x2c
> +#define MTK_NOR_PRGDATA4_REG		0x30
> +#define MTK_NOR_PRGDATA5_REG		0x34
> +#define MTK_NOR_SHREG0_REG		0x38
> +#define MTK_NOR_SHREG1_REG		0x3c
> +#define MTK_NOR_SHREG2_REG		0x40
> +#define MTK_NOR_SHREG3_REG		0x44
> +#define MTK_NOR_SHREG4_REG		0x48
> +#define MTK_NOR_SHREG5_REG		0x4c
> +#define MTK_NOR_SHREG6_REG		0x50
> +#define MTK_NOR_SHREG7_REG		0x54
> +#define MTK_NOR_SHREG8_REG		0x58
> +#define MTK_NOR_SHREG9_REG		0x5c
> +#define MTK_NOR_FLHCFG_REG		0x84
> +#define MTK_NOR_PP_DATA_REG		0x98
> +#define MTK_NOR_PREBUF_STUS_REG		0x9c
> +#define MTK_NOR_INTRSTUS_REG		0xa8
> +#define MTK_NOR_INTREN_REG		0xac
> +#define MTK_NOR_TIME_REG		0x94
> +#define MTK_NOR_CHKSUM_CTL_REG		0xb8
> +#define MTK_NOR_CHKSUM_REG		0xbc
> +#define MTK_NOR_CMD2_REG		0xc0
> +#define MTK_NOR_WRPROT_REG		0xc4
> +#define MTK_NOR_RADR3_REG		0xc8
> +#define MTK_NOR_DUAL_REG		0xcc
> +#define MTK_NOR_DELSEL0_REG		0xa0
> +#define MTK_NOR_DELSEL1_REG		0xa4
> +#define MTK_NOR_DELSEL2_REG		0xd0
> +#define MTK_NOR_DELSEL3_REG		0xd4
> +#define MTK_NOR_DELSEL4_REG		0xd8
> +#define MTK_NOR_CFG1_REG		0x60
> +#define MTK_NOR_CFG2_REG		0x64
> +#define MTK_NOR_CFG3_REG		0x68
> +#define MTK_NOR_STATUS0_REG		0x70
> +#define MTK_NOR_STATUS1_REG		0x74
> +#define MTK_NOR_STATUS2_REG		0x78
> +#define MTK_NOR_STATUS3_REG		0x7c
> +/* commands for mtk nor controller */
> +#define MTK_NOR_READ_CMD		0x0
> +#define MTK_NOR_RDSR_CMD		0x2
> +#define MTK_NOR_PRG_CMD			0x4
> +#define MTK_NOR_WR_CMD			0x10
> +#define MTK_NOR_WRSR_CMD		0x20
> +#define MTK_NOR_PIO_READ_CMD		0x81
> +#define MTK_NOR_WR_BUF_ENABLE		0x1
> +#define MTK_NOR_WR_BUF_DISABLE		0x0
> +#define MTK_NOR_ENABLE_SF_CMD		0x30
> +#define MTK_NOR_DUAD_ADDR_EN		0x8
> +#define MTK_NOR_QUAD_READ_EN		0x4
> +#define MTK_NOR_DUAL_ADDR_EN		0x2
> +#define MTK_NOR_DUAL_READ_EN		0x1
> +#define MTK_NOR_DUAL_DISABLE		0x0
> +#define MTK_NOR_FAST_READ		0x1
> +
> +#define SFLASH_WRBUF_SIZE		128
> +#define MAX_FLASHCOUNT			1
> +#define SFLASHHWNAME_LEN		12
> +#define SFLASH_MAX_DMA_SIZE		(1024 * 8)
> +
> +#define LoWord(d)		((u16)(d & 0x0000ffffL))
> +#define HiWord(d)		((u16)((d >> 16) & 0x0000ffffL))
> +#define LoByte(w)		((u8)(w & 0x00ff))
> +#define HiByte(w)		((u8)(((w) >> 8) & 0x00ff))

NoCamelCasePlease

> +#define LOCAL_BUF_SIZE		(SFLASH_MAX_DMA_SIZE * 20)
> +
> +struct mt8173_nor {
> +	struct mtd_info mtd;
> +	struct spi_nor nor;
> +	struct device *dev;
> +	void __iomem *base;	/* nor flash base address */
> +	struct clk *spi_clk;
> +	struct clk *src_axi_clk;
> +	struct clk *sf_mux_clk;
> +	struct clk *nor_clk;
> +};
> +
> +static void mt8173_nor_set_read_mode(struct mt8173_nor *mt8173_nor)
> +{
> +	struct spi_nor *nor = &mt8173_nor->nor;
> +
> +	switch (nor->flash_read) {
> +	case SPI_NOR_FAST:
> +		writeb(SPINOR_OP_READ_FAST, mt8173_nor->base +
> +		       MTK_NOR_PRGDATA3_REG);
> +		writeb(MTK_NOR_FAST_READ, mt8173_nor->base +
> +		       MTK_NOR_CFG1_REG);
> +		break;
> +	case SPI_NOR_DUAL:
> +		writeb(SPINOR_OP_READ_1_1_2, mt8173_nor->base +
> +		       MTK_NOR_PRGDATA3_REG);
> +		writeb(MTK_NOR_DUAL_READ_EN, mt8173_nor->base +
> +		       MTK_NOR_DUAL_REG);
> +		break;
> +	case SPI_NOR_QUAD:
> +		writeb(SPINOR_OP_READ_1_1_4, mt8173_nor->base +
> +		       MTK_NOR_PRGDATA3_REG);
> +		writeb(MTK_NOR_QUAD_READ_EN, mt8173_nor->base +
> +		       MTK_NOR_DUAL_REG);
> +		break;
> +	default:
> +		writeb(SPINOR_OP_READ, mt8173_nor->base +
> +		       MTK_NOR_PRGDATA3_REG);
> +		writeb(MTK_NOR_DUAL_DISABLE, mt8173_nor->base +
> +		       MTK_NOR_DUAL_REG);
> +		break;
> +	}
> +}
> +
> +static int mt8173_nor_polling_reg(struct mt8173_nor *mt8173_nor, int compare)
> +{
> +	int reg, ret;
> +
> +	ret =  readl_poll_timeout(mt8173_nor->base + MTK_NOR_CMD_REG, reg,
> +				  !(reg & compare), 100, 10000);
> +	if (ret)
> +		dev_err(mt8173_nor->dev, "compare val%02X timeout!\n", compare);
> +	return ret;
> +}
> +
> +static int mt8173_nor_execute_cmd(struct mt8173_nor *mt8173_nor, u8 cmdval)
> +{
> +	u8 val = cmdval & 0x1f;
> +
> +	writeb(cmdval, mt8173_nor->base + MTK_NOR_CMD_REG);
> +	return mt8173_nor_polling_reg(mt8173_nor, val);

mt8173_nor_polling_reg() is used only once here. You can inline the code
here.

> +}
> +
> +static int mt8173_nor_set_cmd(struct mt8173_nor *mt8173_nor, int addr,
> +			      int len, int op)
> +{
> +	writeb(op, mt8173_nor->base + MTK_NOR_PRGDATA5_REG);
> +	/* reset the following register */

We see that some register writes follow, this comment doesn't contain
any additional information.

> +	writeb(LoByte(HiWord(addr)), mt8173_nor->base + MTK_NOR_PRGDATA4_REG);
> +	writeb(HiByte(LoWord(addr)), mt8173_nor->base + MTK_NOR_PRGDATA3_REG);
> +	writeb(LoByte(LoWord(addr)), mt8173_nor->base + MTK_NOR_PRGDATA2_REG);

Just do a:

(addr >> 16) & 0xff
(addr >> 8) & 0xff
addr & 0xff

It's a pattern every lowlevel programmer recognizes without thinking
about it. Same for the other places where these defines are used.

> +	writeb(len, mt8173_nor->base + MTK_NOR_CNT_REG);
> +	return mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_PRG_CMD);
> +}
> +
> +static int mt8173_nor_get_para(struct mt8173_nor *mt8173_nor, u8 *buf, int len)
> +{
> +	if (len > 1) {
> +		/* read JEDEC ID need 4 bytes commands */
> +		mt8173_nor_set_cmd(mt8173_nor, 0, 32, SPINOR_OP_RDID);
> +		buf[2] = readb(mt8173_nor->base + MTK_NOR_SHREG0_REG);
> +		buf[1] = readb(mt8173_nor->base + MTK_NOR_SHREG1_REG);
> +		buf[0] = readb(mt8173_nor->base + MTK_NOR_SHREG2_REG);
> +	} else {
> +		if (mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_RDSR_CMD)) {
> +			dev_err(mt8173_nor->dev, "read status failed!\n");
> +			return -EINVAL;
> +		}
> +		*buf = readb(mt8173_nor->base + MTK_NOR_RDSR_REG);
> +	}
> +	return 0;
> +}
> +
> +/* cmd1 sent to nor flash, cmd2 write to nor controller */
> +static int mt8173_nor_set_para(struct mt8173_nor *mt8173_nor, int cmd1,
> +			       int cmd2)
> +{
> +	if (mt8173_nor_set_cmd(mt8173_nor, 0, 8, SPINOR_OP_WREN)) {
> +		dev_err(mt8173_nor->dev,
> +			"write enable failed in write protect!\n");
> +		return -EINVAL;
> +	}
> +	writeb(cmd1, mt8173_nor->base + MTK_NOR_PRGDATA5_REG);
> +	writeb(8, mt8173_nor->base + MTK_NOR_CNT_REG);
> +	if (mt8173_nor_execute_cmd(mt8173_nor, cmd2)) {
> +		dev_err(mt8173_nor->dev, "execute cmd failed!\n");

mt8173_nor_execute_cmd() will already have printed an error message.

> +		return -EINVAL;
> +	}
> +	return 0;
> +}
> +
> +static int mt8173_nor_write_buffer_enable(struct mt8173_nor *mt8173_nor)
> +{
> +	u8 reg, ret;
> +
> +	writel(MTK_NOR_WR_BUF_ENABLE, mt8173_nor->base + MTK_NOR_CFG2_REG);
> +	ret =  readb_poll_timeout(mt8173_nor->base + MTK_NOR_CFG2_REG, reg,
> +				  0x01 == (reg & 0x01), 100, 10000);
> +	if (ret)
> +		dev_err(mt8173_nor->dev, "timeout!\n");
> +	return ret;
> +}
> +
> +static int mt8173_nor_write_buffer_disable(struct mt8173_nor *mt8173_nor)
> +{
> +	u8 reg, ret;
> +
> +	writel(MTK_NOR_WR_BUF_DISABLE, mt8173_nor->base + MTK_NOR_CFG2_REG);
> +	ret =  readb_poll_timeout(mt8173_nor->base + MTK_NOR_CFG2_REG, reg,
> +				  MTK_NOR_WR_BUF_DISABLE == (reg & 0xf), 100,
> +				  10000);
> +	if (ret)
> +		dev_err(mt8173_nor->dev, "compare timeout!\n");
> +	return ret;
> +}
> +
> +static int mt8173_nor_erase_sector(struct spi_nor *nor, loff_t offset)
> +{
> +	struct mt8173_nor *mt8173_nor = nor->priv;
> +
> +	if (mt8173_nor_set_cmd(mt8173_nor, 0, 8, SPINOR_OP_WREN)) {
> +		dev_err(mt8173_nor->dev,
> +			"write enable failed in erase sector!\n");
> +		return -EINVAL;
> +	}
> +
> +	mt8173_nor_set_cmd(mt8173_nor, (int)offset, 32, SPINOR_OP_BE_4K);
> +	return 0;
> +}
> +
> +static int mt8173_nor_read_hw(struct mt8173_nor *mt8173_nor, int addr, int len,
> +			      int *retlen, u8 *buf)
> +{
> +	int ret = 0, i;
> +
> +	mt8173_nor_set_read_mode(mt8173_nor);
> +	writeb(HiByte(HiWord(addr)), mt8173_nor->base + MTK_NOR_RADR3_REG);
> +	writeb(LoByte(HiWord(addr)), mt8173_nor->base + MTK_NOR_RADR2_REG);
> +	writeb(HiByte(LoWord(addr)), mt8173_nor->base + MTK_NOR_RADR1_REG);
> +	writeb(LoByte(LoWord(addr)), mt8173_nor->base + MTK_NOR_RADR0_REG);
> +
> +	for (i = 0; i < len; i++, (*retlen)++) {
> +		if (mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_PIO_READ_CMD)) {
> +			dev_err(mt8173_nor->dev, "read flash failed!\n");
> +			return -EINVAL;
> +		}
> +		buf[i] = readb(mt8173_nor->base + MTK_NOR_RDATA_REG);
> +	}
> +	return ret;

ret will always be 0 here, drop the ret variable.

> +}
> +
> +static int mt8173_nor_read(struct spi_nor *nor, loff_t from, size_t len,
> +			   size_t *retlen, u_char *buf)
> +{
> +	struct mt8173_nor *mt8173_nor = nor->priv;
> +
> +	return mt8173_nor_read_hw(mt8173_nor, (int)from, (int)len,
> +				 (int *)retlen, (u8 *)buf);

mt8173_nor_read_hw is used only once here, no need for a separate
function.

> +}
> +
> +static int mt8173_nor_write_single_byte(struct mt8173_nor *mt8173_nor,
> +					int u4addr, u8 u1data)
> +{
> +	if (u4addr >= mt8173_nor->mtd.size) {
> +		dev_err(mt8173_nor->dev, "invalid write address!\n");
> +		return -EINVAL;
> +	}
> +
> +	writeb(u1data, mt8173_nor->base + MTK_NOR_WDATA_REG);
> +	writeb(LoByte(HiWord(u4addr)), mt8173_nor->base + MTK_NOR_RADR2_REG);
> +	writeb(HiByte(LoWord(u4addr)), mt8173_nor->base + MTK_NOR_RADR1_REG);
> +	writeb(LoByte(LoWord(u4addr)), mt8173_nor->base + MTK_NOR_RADR0_REG);
> +
> +	if (mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_WR_CMD)) {
> +		dev_err(mt8173_nor->dev, "write byte offset%08x\n", u4addr);
> +		return -EINVAL;
> +	}
> +	return 0;
> +}
> +
> +static int mt8173_nor_write_buffer(struct mt8173_nor *mt8173_nor, int u4addr,
> +				   int u4len, const u8 *buf)
> +{
> +	int i, j, bufidx, data;
> +
> +	if (!buf)
> +		return -EINVAL;
> +
> +	writeb(LoByte(HiWord(u4addr)), mt8173_nor->base + MTK_NOR_RADR2_REG);
> +	writeb(HiByte(LoWord(u4addr)), mt8173_nor->base + MTK_NOR_RADR1_REG);
> +	writeb(LoByte(LoWord(u4addr)), mt8173_nor->base + MTK_NOR_RADR0_REG);
> +
> +	bufidx = 0;
> +	for (i = 0; i < u4len; i += 4) {
> +		for (j = 0; j < 4; j++) {
> +			(*((u8 *)&data + j)) = buf[bufidx];
> +			bufidx++;
> +		}
> +		writel(data, mt8173_nor->base + MTK_NOR_PP_DATA_REG);
> +	}
> +
> +	if (mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_WR_CMD)) {
> +		dev_err(mt8173_nor->dev, "write buffer offset:%08x\n", u4addr);
> +		return -EINVAL;
> +	}
> +	return 0;
> +}
> +
> +static void mt8173_nor_write(struct spi_nor *nor, loff_t to, size_t len,
> +			     size_t *retlen, const u_char *buf)
> +{
> +	struct mt8173_nor *mt8173_nor = nor->priv;
> +	size_t i;
> +
> +	if (nor->page_size == len) {
> +		if (mt8173_nor_write_buffer_enable(mt8173_nor))
> +			dev_err(mt8173_nor->dev, "write buffer enable failed !\n");
> +		while (len > 0) {
> +			mt8173_nor_write_buffer(mt8173_nor, to,
> +						SFLASH_WRBUF_SIZE, buf);
> +			len -= SFLASH_WRBUF_SIZE;
> +			to += SFLASH_WRBUF_SIZE;
> +			buf += SFLASH_WRBUF_SIZE;
> +			(*retlen) += SFLASH_WRBUF_SIZE;
> +		}
> +		if (mt8173_nor_write_buffer_disable(mt8173_nor))
> +			dev_err(mt8173_nor->dev, "write buffer disable failed !\n");
> +	} else {
> +		for (i = 0; i < len; i++,  (*retlen)++) {
> +			if (mt8173_nor_write_single_byte(mt8173_nor, to, *buf))
> +				dev_err(mt8173_nor->dev, "write byte failed !\n");
> +			to++;
> +			buf++;
> +		}
> +	}
> +}

Instead of using the buffer write method only for page_size sized writes
I would expect a behaviour of this function like:

	while (len > SFLASH_WRBUF_SIZE) {
		write_buffer();
		len -= SFLASH_WRBUF_SIZE;
	}

	while (len) {
		write_single_byte();
		len--;
	}

> +
> +static int mt8173_nor_read_reg(struct spi_nor *nor, u8 opcode, u8 *buf, int len)
> +{
> +	int ret = 0;
> +	struct mt8173_nor *mt8173_nor = nor->priv;
> +	/* mtk nor controller haven't supoort SPINOR_OP_RDCR */
> +	if (opcode == SPINOR_OP_RDID || opcode == SPINOR_OP_RDSR)
> +		ret = mt8173_nor_get_para(mt8173_nor, buf, len);
> +	else
> +		dev_warn(mt8173_nor->dev, "invalid cmd %d\n", opcode);
> +
> +	return ret;
> +}
> +
> +static int mt8173_nor_write_reg(struct spi_nor *nor, u8 opcode, u8 *buf,
> +				int len, int write_enable)
> +{
> +	int ret, cmd_to_nor, cmd_to_controller;
> +	struct mt8173_nor *mt8173_nor = nor->priv;
> +
> +	if (opcode == SPINOR_OP_WRSR || opcode == SPINOR_OP_CHIP_ERASE) {
> +		if (len > 0) {
> +			cmd_to_nor = *buf;
> +			cmd_to_controller = MTK_NOR_WRSR_CMD;
> +		} else {
> +			cmd_to_nor = opcode;
> +			cmd_to_controller = MTK_NOR_PRG_CMD;
> +		}
> +		ret = mt8173_nor_set_para(mt8173_nor, cmd_to_nor,
> +					  cmd_to_controller);
> +	} else if (opcode == SPINOR_OP_WREN || opcode == SPINOR_OP_WRDI) {
> +		ret = mt8173_nor_set_cmd(mt8173_nor, 0, 8, opcode);
> +	} else {
> +		dev_warn(mt8173_nor->dev, "have not support cmd %d\n", opcode);
> +		ret = -EINVAL;
> +	}
> +	return ret;
> +}
> +
> +static int __init mtk_nor_init(struct mt8173_nor *mt8173_nor,
> +			       struct mtd_part_parser_data ppdata)

Why a copy and not a pointer to struct mtd_part_parser_data?

> +{
> +	int ret;
> +	struct spi_nor *nor;
> +	struct mtd_info *mtd;
> +
> +	writel(MTK_NOR_ENABLE_SF_CMD, mt8173_nor->base + MTK_NOR_WRPROT_REG);
> +	nor = &mt8173_nor->nor;
> +	mtd = &mt8173_nor->mtd;
> +	nor->mtd = mt8173_nor->mtd;
> +	nor->dev = mt8173_nor->dev;
> +	nor->priv = mt8173_nor;
> +	mtd->priv = nor;
> +
> +	/* fill the hooks to spi nor */
> +	nor->read = mt8173_nor_read;
> +	nor->read_reg = mt8173_nor_read_reg;
> +	nor->write = mt8173_nor_write;
> +	nor->write_reg = mt8173_nor_write_reg;
> +	nor->erase = mt8173_nor_erase_sector;
> +	nor->mtd.owner = THIS_MODULE;
> +	nor->mtd.name = "mtk_nor";
> +	/* initialized with NULL */
> +	ret = spi_nor_scan(nor, NULL, SPI_NOR_DUAL);
> +	if (ret) {
> +		dev_err(mt8173_nor->dev, "spi_nor_scan failed !\n");
> +		return -EINVAL;

Just forward the error from spi_nor_scan.

> +	}
> +	dev_dbg(mt8173_nor->dev, "mtd->size :0x%llx!\n", mtd->size);
> +	ret = mtd_device_parse_register(&nor->mtd, NULL, &ppdata, NULL, 0);
> +
> +	return ret;
> +}
> +
> +static int mtk_nor_drv_probe(struct platform_device *pdev)
> +{
> +	struct device_node *np = pdev->dev.of_node;
> +	struct mtd_part_parser_data ppdata;
> +	struct resource *res;
> +	int ret;
> +	struct mt8173_nor *mt8173_nor = devm_kzalloc(&pdev->dev,
> +		sizeof(*mt8173_nor), GFP_KERNEL);
> +
> +	if (!pdev->dev.of_node) {
> +		dev_err(&pdev->dev, "No DT found\n");
> +		return -EINVAL;
> +	}
> +
> +	if (!mt8173_nor)
> +		return -ENOMEM;
> +	platform_set_drvdata(pdev, mt8173_nor);
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	mt8173_nor->base = devm_ioremap_resource(&pdev->dev, res);
> +	if (IS_ERR(mt8173_nor->base)) {
> +		ret = PTR_ERR(mt8173_nor->base);
> +		goto nor_free;
> +	}
> +
> +	mt8173_nor->spi_clk = devm_clk_get(&pdev->dev, "spi_clk");
> +	if (IS_ERR(mt8173_nor->spi_clk)) {
> +		ret = PTR_ERR(mt8173_nor->spi_clk);
> +		goto nor_free;
> +	}
> +
> +	mt8173_nor->src_axi_clk = devm_clk_get(&pdev->dev, "axi_clk");
> +	if (IS_ERR(mt8173_nor->src_axi_clk)) {
> +		ret = PTR_ERR(mt8173_nor->src_axi_clk);
> +		goto nor_free;
> +	}
> +
> +	mt8173_nor->sf_mux_clk = devm_clk_get(&pdev->dev, "mux_clk");
> +	if (IS_ERR(mt8173_nor->sf_mux_clk)) {
> +		ret = PTR_ERR(mt8173_nor->sf_mux_clk);
> +		goto nor_free;
> +	}
> +
> +	mt8173_nor->nor_clk = devm_clk_get(&pdev->dev, "sf_clk");
> +	if (IS_ERR(mt8173_nor->nor_clk)) {
> +		ret = PTR_ERR(mt8173_nor->nor_clk);
> +		goto nor_free;
> +	}
> +
> +	mt8173_nor->dev = &pdev->dev;
> +	clk_prepare_enable(mt8173_nor->spi_clk);
> +	clk_prepare_enable(mt8173_nor->src_axi_clk);
> +	clk_prepare_enable(mt8173_nor->sf_mux_clk);
> +	clk_prepare_enable(mt8173_nor->nor_clk);
> +	clk_set_parent(mt8173_nor->nor_clk, mt8173_nor->sf_mux_clk);

sf_mux_clk is inherently enabled when you enable one of its child
clocks, like nor_clk in this case, so you don't have to enable it
explicitly.
Also putting knowledge of the SoCs clock layout into the driver is a bad
idea. There is the assigned-clock-parents binding which you can use here
for assigning the clock parent.

> +
> +	ppdata.of_node = np;
> +	ret = mtk_nor_init(mt8173_nor, ppdata);
> +
> +nor_free:
> +	return ret;
> +}
> +
> +static int mtk_nor_drv_remove(struct platform_device *pdev)
> +{
> +	struct mt8173_nor *mt8173_nor = platform_get_drvdata(pdev);
> +
> +	clk_disable_unprepare(mt8173_nor->spi_clk);
> +	clk_disable_unprepare(mt8173_nor->src_axi_clk);
> +	clk_disable_unprepare(mt8173_nor->sf_mux_clk);
> +	clk_disable_unprepare(mt8173_nor->nor_clk);
> +	mtd_device_unregister(&mt8173_nor->mtd);

This order is wrong. You should not disable clocks on a device that
might be active. You should unregister it first and disable the clocks
afterwards.

Sascha


-- 
Pengutronix e.K.                           |                             |
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[PATCH 2/3] mtd: mtk-nor: mtk serial flash controller driver

[Lothar Waßmann]

Hi,

> > +	writeb(len, mt8173_nor->base + MTK_NOR_CNT_REG);
> > +	return mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_PRG_CMD);
> > +}
> > +
> > +static int mt8173_nor_get_para(struct mt8173_nor *mt8173_nor, u8 *buf, int len)
> > +{
> > +	if (len > 1) {
> > +		/* read JEDEC ID need 4 bytes commands */
> > +		mt8173_nor_set_cmd(mt8173_nor, 0, 32, SPINOR_OP_RDID);
> > +		buf[2] = readb(mt8173_nor->base + MTK_NOR_SHREG0_REG);
> > +		buf[1] = readb(mt8173_nor->base + MTK_NOR_SHREG1_REG);
> > +		buf[0] = readb(mt8173_nor->base + MTK_NOR_SHREG2_REG);
> > +	} else {
> > +		if (mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_RDSR_CMD)) {
> > +			dev_err(mt8173_nor->dev, "read status failed!\n");
> > +			return -EINVAL;
> > +		}
> > +		*buf = readb(mt8173_nor->base + MTK_NOR_RDSR_REG);
> > +	}
> > +	return 0;
> > +}
> > +
> > +/* cmd1 sent to nor flash, cmd2 write to nor controller */
> > +static int mt8173_nor_set_para(struct mt8173_nor *mt8173_nor, int cmd1,
> > +			       int cmd2)
> > +{
> > +	if (mt8173_nor_set_cmd(mt8173_nor, 0, 8, SPINOR_OP_WREN)) {
> > +		dev_err(mt8173_nor->dev,
> > +			"write enable failed in write protect!\n");
> > +		return -EINVAL;
> > +	}
> > +	writeb(cmd1, mt8173_nor->base + MTK_NOR_PRGDATA5_REG);
> > +	writeb(8, mt8173_nor->base + MTK_NOR_CNT_REG);
> > +	if (mt8173_nor_execute_cmd(mt8173_nor, cmd2)) {
> > +		dev_err(mt8173_nor->dev, "execute cmd failed!\n");
> 
> mt8173_nor_execute_cmd() will already have printed an error message.
> 
And mt8173_nor_execute_cmd()/mt8173_nor_set_cmd() returned an error
code which should be promoted to the caller rather than
inventing a new one.
The same for other instances of this code fragment.


Lothar Wa?mann

[PATCH 2/3] mtd: mtk-nor: mtk serial flash controller driver

[bayi.cheng]

On Wed, 2015-09-09 at 15:00 +0200, Lothar Wa?mann wrote:
> Hi,
> 
> > > +	writeb(len, mt8173_nor->base + MTK_NOR_CNT_REG);
> > > +	return mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_PRG_CMD);
> > > +}
> > > +
> > > +static int mt8173_nor_get_para(struct mt8173_nor *mt8173_nor, u8 *buf, int len)
> > > +{
> > > +	if (len > 1) {
> > > +		/* read JEDEC ID need 4 bytes commands */
> > > +		mt8173_nor_set_cmd(mt8173_nor, 0, 32, SPINOR_OP_RDID);
> > > +		buf[2] = readb(mt8173_nor->base + MTK_NOR_SHREG0_REG);
> > > +		buf[1] = readb(mt8173_nor->base + MTK_NOR_SHREG1_REG);
> > > +		buf[0] = readb(mt8173_nor->base + MTK_NOR_SHREG2_REG);
> > > +	} else {
> > > +		if (mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_RDSR_CMD)) {
> > > +			dev_err(mt8173_nor->dev, "read status failed!\n");
> > > +			return -EINVAL;
> > > +		}
> > > +		*buf = readb(mt8173_nor->base + MTK_NOR_RDSR_REG);
> > > +	}
> > > +	return 0;
> > > +}
> > > +
> > > +/* cmd1 sent to nor flash, cmd2 write to nor controller */
> > > +static int mt8173_nor_set_para(struct mt8173_nor *mt8173_nor, int cmd1,
> > > +			       int cmd2)
> > > +{
> > > +	if (mt8173_nor_set_cmd(mt8173_nor, 0, 8, SPINOR_OP_WREN)) {
> > > +		dev_err(mt8173_nor->dev,
> > > +			"write enable failed in write protect!\n");
> > > +		return -EINVAL;
> > > +	}
> > > +	writeb(cmd1, mt8173_nor->base + MTK_NOR_PRGDATA5_REG);
> > > +	writeb(8, mt8173_nor->base + MTK_NOR_CNT_REG);
> > > +	if (mt8173_nor_execute_cmd(mt8173_nor, cmd2)) {
> > > +		dev_err(mt8173_nor->dev, "execute cmd failed!\n");
> > 
> > mt8173_nor_execute_cmd() will already have printed an error message.
> > 
> And mt8173_nor_execute_cmd()/mt8173_nor_set_cmd() returned an error
> code which should be promoted to the caller rather than
> inventing a new one.
> The same for other instances of this code fragment.
Sorry for later reply ,and Thanks for your instruct, and I will promote
the error code to the caller. 
> 
> 
> Lothar Wa?mann
> 
> _______________________________________________
> Linux-mediatek mailing list
> Linux-mediatek at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-mediatek

[PATCH 2/3] mtd: mtk-nor: mtk serial flash controller driver

[bayi.cheng]

On Wed, 2015-09-09 at 08:37 +0200, Sascha Hauer wrote:
> On Tue, Sep 08, 2015 at 05:49:55PM +0800, Bayi Cheng wrote:
> > add spi nor flash driver for mediatek controller
> > 
> > Signed-off-by: Bayi Cheng <bayi.cheng@mediatek.com>
> > ---
> >  drivers/mtd/spi-nor/Kconfig   |   7 +
> >  drivers/mtd/spi-nor/Makefile  |   1 +
> >  drivers/mtd/spi-nor/mtk_nor.c | 533 ++++++++++++++++++++++++++++++++++++++++++
> >  3 files changed, 541 insertions(+)
> >  create mode 100644 drivers/mtd/spi-nor/mtk_nor.c
> > 
> > diff --git a/drivers/mtd/spi-nor/Kconfig b/drivers/mtd/spi-nor/Kconfig
> > index 89bf4c1..f433890 100644
> > --- a/drivers/mtd/spi-nor/Kconfig
> > +++ b/drivers/mtd/spi-nor/Kconfig
> > @@ -7,6 +7,13 @@ menuconfig MTD_SPI_NOR
> >  
> >  if MTD_SPI_NOR
> >  
> > +config MTD_MT81xx_NOR
> > +	tristate "Support SPI flash Controller MTD_MT81xx_NOR"
> > +	help
> > +	  This enables access to SPI Nor flash, using MTD_MT81XX_NOR controller.
> > +	  This controller does nor support generic SPI BUS, It only supports
> > +	  SPI NOR Flash.
> > +
> >  config MTD_SPI_NOR_USE_4K_SECTORS
> >  	bool "Use small 4096 B erase sectors"
> >  	default y
> > diff --git a/drivers/mtd/spi-nor/Makefile b/drivers/mtd/spi-nor/Makefile
> > index e53333e..2f4fe62 100644
> > --- a/drivers/mtd/spi-nor/Makefile
> > +++ b/drivers/mtd/spi-nor/Makefile
> > @@ -1,3 +1,4 @@
> > +obj-$(CONFIG_MTD_MT81xx_NOR)	+= mtk_nor.o
> >  obj-$(CONFIG_MTD_SPI_NOR)	+= spi-nor.o
> >  obj-$(CONFIG_SPI_FSL_QUADSPI)	+= fsl-quadspi.o
> >  obj-$(CONFIG_SPI_NXP_SPIFI)	+= nxp-spifi.o
> > diff --git a/drivers/mtd/spi-nor/mtk_nor.c b/drivers/mtd/spi-nor/mtk_nor.c
> > new file mode 100644
> > index 0000000..e675fb6
> > --- /dev/null
> > +++ b/drivers/mtd/spi-nor/mtk_nor.c
> > @@ -0,0 +1,533 @@
> > +/*
> > + * Copyright (c) 2015 MediaTek Inc.
> > + * Author: Bayi.Cheng <bayi.cheng@mediatek.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.
> > + *
> > + * This program is distributed in the hope that it will be useful,
> > + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> > + * GNU General Public License for more details.
> > + */
> > +
> > +#include <linux/clk.h>
> > +#include <linux/delay.h>
> > +#include <linux/device.h>
> > +#include <linux/init.h>
> > +#include <linux/io.h>
> > +#include <linux/iopoll.h>
> > +#include <linux/ioport.h>
> > +#include <linux/math64.h>
> > +#include <linux/module.h>
> > +#include <linux/mtd/mtd.h>
> > +#include <linux/mutex.h>
> > +#include <linux/of.h>
> > +#include <linux/of_device.h>
> > +#include <linux/of_gpio.h>
> > +#include <linux/pinctrl/consumer.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/slab.h>
> > +#include <linux/mtd/mtd.h>
> > +#include <linux/mtd/partitions.h>
> > +#include <linux/mtd/spi-nor.h>
> > +
> > +#define MTK_NOR_CMD_REG			0x00
> > +#define MTK_NOR_CNT_REG			0x04
> > +#define MTK_NOR_RDSR_REG		0x08
> > +#define MTK_NOR_RDATA_REG		0x0c
> > +#define MTK_NOR_RADR0_REG		0x10
> > +#define MTK_NOR_RADR1_REG		0x14
> > +#define MTK_NOR_RADR2_REG		0x18
> > +#define MTK_NOR_WDATA_REG		0x1c
> > +#define MTK_NOR_PRGDATA0_REG		0x20
> > +#define MTK_NOR_PRGDATA1_REG		0x24
> > +#define MTK_NOR_PRGDATA2_REG		0x28
> > +#define MTK_NOR_PRGDATA3_REG		0x2c
> > +#define MTK_NOR_PRGDATA4_REG		0x30
> > +#define MTK_NOR_PRGDATA5_REG		0x34
> > +#define MTK_NOR_SHREG0_REG		0x38
> > +#define MTK_NOR_SHREG1_REG		0x3c
> > +#define MTK_NOR_SHREG2_REG		0x40
> > +#define MTK_NOR_SHREG3_REG		0x44
> > +#define MTK_NOR_SHREG4_REG		0x48
> > +#define MTK_NOR_SHREG5_REG		0x4c
> > +#define MTK_NOR_SHREG6_REG		0x50
> > +#define MTK_NOR_SHREG7_REG		0x54
> > +#define MTK_NOR_SHREG8_REG		0x58
> > +#define MTK_NOR_SHREG9_REG		0x5c
> > +#define MTK_NOR_FLHCFG_REG		0x84
> > +#define MTK_NOR_PP_DATA_REG		0x98
> > +#define MTK_NOR_PREBUF_STUS_REG		0x9c
> > +#define MTK_NOR_INTRSTUS_REG		0xa8
> > +#define MTK_NOR_INTREN_REG		0xac
> > +#define MTK_NOR_TIME_REG		0x94
> > +#define MTK_NOR_CHKSUM_CTL_REG		0xb8
> > +#define MTK_NOR_CHKSUM_REG		0xbc
> > +#define MTK_NOR_CMD2_REG		0xc0
> > +#define MTK_NOR_WRPROT_REG		0xc4
> > +#define MTK_NOR_RADR3_REG		0xc8
> > +#define MTK_NOR_DUAL_REG		0xcc
> > +#define MTK_NOR_DELSEL0_REG		0xa0
> > +#define MTK_NOR_DELSEL1_REG		0xa4
> > +#define MTK_NOR_DELSEL2_REG		0xd0
> > +#define MTK_NOR_DELSEL3_REG		0xd4
> > +#define MTK_NOR_DELSEL4_REG		0xd8
> > +#define MTK_NOR_CFG1_REG		0x60
> > +#define MTK_NOR_CFG2_REG		0x64
> > +#define MTK_NOR_CFG3_REG		0x68
> > +#define MTK_NOR_STATUS0_REG		0x70
> > +#define MTK_NOR_STATUS1_REG		0x74
> > +#define MTK_NOR_STATUS2_REG		0x78
> > +#define MTK_NOR_STATUS3_REG		0x7c
> > +/* commands for mtk nor controller */
> > +#define MTK_NOR_READ_CMD		0x0
> > +#define MTK_NOR_RDSR_CMD		0x2
> > +#define MTK_NOR_PRG_CMD			0x4
> > +#define MTK_NOR_WR_CMD			0x10
> > +#define MTK_NOR_WRSR_CMD		0x20
> > +#define MTK_NOR_PIO_READ_CMD		0x81
> > +#define MTK_NOR_WR_BUF_ENABLE		0x1
> > +#define MTK_NOR_WR_BUF_DISABLE		0x0
> > +#define MTK_NOR_ENABLE_SF_CMD		0x30
> > +#define MTK_NOR_DUAD_ADDR_EN		0x8
> > +#define MTK_NOR_QUAD_READ_EN		0x4
> > +#define MTK_NOR_DUAL_ADDR_EN		0x2
> > +#define MTK_NOR_DUAL_READ_EN		0x1
> > +#define MTK_NOR_DUAL_DISABLE		0x0
> > +#define MTK_NOR_FAST_READ		0x1
> > +
> > +#define SFLASH_WRBUF_SIZE		128
> > +#define MAX_FLASHCOUNT			1
> > +#define SFLASHHWNAME_LEN		12
> > +#define SFLASH_MAX_DMA_SIZE		(1024 * 8)
> > +
> > +#define LoWord(d)		((u16)(d & 0x0000ffffL))
> > +#define HiWord(d)		((u16)((d >> 16) & 0x0000ffffL))
> > +#define LoByte(w)		((u8)(w & 0x00ff))
> > +#define HiByte(w)		((u8)(((w) >> 8) & 0x00ff))
> 
> NoCamelCasePlease
OK, I will fix it. and sorry for later reply !
> 
> > +#define LOCAL_BUF_SIZE		(SFLASH_MAX_DMA_SIZE * 20)
> > +
> > +struct mt8173_nor {
> > +	struct mtd_info mtd;
> > +	struct spi_nor nor;
> > +	struct device *dev;
> > +	void __iomem *base;	/* nor flash base address */
> > +	struct clk *spi_clk;
> > +	struct clk *src_axi_clk;
> > +	struct clk *sf_mux_clk;
> > +	struct clk *nor_clk;
> > +};
> > +
> > +static void mt8173_nor_set_read_mode(struct mt8173_nor *mt8173_nor)
> > +{
> > +	struct spi_nor *nor = &mt8173_nor->nor;
> > +
> > +	switch (nor->flash_read) {
> > +	case SPI_NOR_FAST:
> > +		writeb(SPINOR_OP_READ_FAST, mt8173_nor->base +
> > +		       MTK_NOR_PRGDATA3_REG);
> > +		writeb(MTK_NOR_FAST_READ, mt8173_nor->base +
> > +		       MTK_NOR_CFG1_REG);
> > +		break;
> > +	case SPI_NOR_DUAL:
> > +		writeb(SPINOR_OP_READ_1_1_2, mt8173_nor->base +
> > +		       MTK_NOR_PRGDATA3_REG);
> > +		writeb(MTK_NOR_DUAL_READ_EN, mt8173_nor->base +
> > +		       MTK_NOR_DUAL_REG);
> > +		break;
> > +	case SPI_NOR_QUAD:
> > +		writeb(SPINOR_OP_READ_1_1_4, mt8173_nor->base +
> > +		       MTK_NOR_PRGDATA3_REG);
> > +		writeb(MTK_NOR_QUAD_READ_EN, mt8173_nor->base +
> > +		       MTK_NOR_DUAL_REG);
> > +		break;
> > +	default:
> > +		writeb(SPINOR_OP_READ, mt8173_nor->base +
> > +		       MTK_NOR_PRGDATA3_REG);
> > +		writeb(MTK_NOR_DUAL_DISABLE, mt8173_nor->base +
> > +		       MTK_NOR_DUAL_REG);
> > +		break;
> > +	}
> > +}
> > +
> > +static int mt8173_nor_polling_reg(struct mt8173_nor *mt8173_nor, int compare)
> > +{
> > +	int reg, ret;
> > +
> > +	ret =  readl_poll_timeout(mt8173_nor->base + MTK_NOR_CMD_REG, reg,
> > +				  !(reg & compare), 100, 10000);
> > +	if (ret)
> > +		dev_err(mt8173_nor->dev, "compare val%02X timeout!\n", compare);
> > +	return ret;
> > +}
> > +
> > +static int mt8173_nor_execute_cmd(struct mt8173_nor *mt8173_nor, u8 cmdval)
> > +{
> > +	u8 val = cmdval & 0x1f;
> > +
> > +	writeb(cmdval, mt8173_nor->base + MTK_NOR_CMD_REG);
> > +	return mt8173_nor_polling_reg(mt8173_nor, val);
> 
> mt8173_nor_polling_reg() is used only once here. You can inline the code
> here.
> 
Ok, I will fixed it .
> > +}
> > +
> > +static int mt8173_nor_set_cmd(struct mt8173_nor *mt8173_nor, int addr,
> > +			      int len, int op)
> > +{
> > +	writeb(op, mt8173_nor->base + MTK_NOR_PRGDATA5_REG);
> > +	/* reset the following register */
> 
> We see that some register writes follow, this comment doesn't contain
> any additional information.
I will added more comments here .
> 
> > +	writeb(LoByte(HiWord(addr)), mt8173_nor->base + MTK_NOR_PRGDATA4_REG);
> > +	writeb(HiByte(LoWord(addr)), mt8173_nor->base + MTK_NOR_PRGDATA3_REG);
> > +	writeb(LoByte(LoWord(addr)), mt8173_nor->base + MTK_NOR_PRGDATA2_REG);
> 
> Just do a:
> 
> (addr >> 16) & 0xff
> (addr >> 8) & 0xff
> addr & 0xff
> 
> It's a pattern every lowlevel programmer recognizes without thinking
> about it. Same for the other places where these defines are used.
Yes, Thanks for your remind!
> 
> > +	writeb(len, mt8173_nor->base + MTK_NOR_CNT_REG);
> > +	return mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_PRG_CMD);
> > +}
> > +
> > +static int mt8173_nor_get_para(struct mt8173_nor *mt8173_nor, u8 *buf, int len)
> > +{
> > +	if (len > 1) {
> > +		/* read JEDEC ID need 4 bytes commands */
> > +		mt8173_nor_set_cmd(mt8173_nor, 0, 32, SPINOR_OP_RDID);
> > +		buf[2] = readb(mt8173_nor->base + MTK_NOR_SHREG0_REG);
> > +		buf[1] = readb(mt8173_nor->base + MTK_NOR_SHREG1_REG);
> > +		buf[0] = readb(mt8173_nor->base + MTK_NOR_SHREG2_REG);
> > +	} else {
> > +		if (mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_RDSR_CMD)) {
> > +			dev_err(mt8173_nor->dev, "read status failed!\n");
> > +			return -EINVAL;
> > +		}
> > +		*buf = readb(mt8173_nor->base + MTK_NOR_RDSR_REG);
> > +	}
> > +	return 0;
> > +}
> > +
> > +/* cmd1 sent to nor flash, cmd2 write to nor controller */
> > +static int mt8173_nor_set_para(struct mt8173_nor *mt8173_nor, int cmd1,
> > +			       int cmd2)
> > +{
> > +	if (mt8173_nor_set_cmd(mt8173_nor, 0, 8, SPINOR_OP_WREN)) {
> > +		dev_err(mt8173_nor->dev,
> > +			"write enable failed in write protect!\n");
> > +		return -EINVAL;
> > +	}
> > +	writeb(cmd1, mt8173_nor->base + MTK_NOR_PRGDATA5_REG);
> > +	writeb(8, mt8173_nor->base + MTK_NOR_CNT_REG);
> > +	if (mt8173_nor_execute_cmd(mt8173_nor, cmd2)) {
> > +		dev_err(mt8173_nor->dev, "execute cmd failed!\n");
> 
> mt8173_nor_execute_cmd() will already have printed an error message.
OK, I will remove this error message!
> 
> > +		return -EINVAL;
> > +	}
> > +	return 0;
> > +}
> > +
> > +static int mt8173_nor_write_buffer_enable(struct mt8173_nor *mt8173_nor)
> > +{
> > +	u8 reg, ret;
> > +
> > +	writel(MTK_NOR_WR_BUF_ENABLE, mt8173_nor->base + MTK_NOR_CFG2_REG);
> > +	ret =  readb_poll_timeout(mt8173_nor->base + MTK_NOR_CFG2_REG, reg,
> > +				  0x01 == (reg & 0x01), 100, 10000);
> > +	if (ret)
> > +		dev_err(mt8173_nor->dev, "timeout!\n");
> > +	return ret;
> > +}
> > +
> > +static int mt8173_nor_write_buffer_disable(struct mt8173_nor *mt8173_nor)
> > +{
> > +	u8 reg, ret;
> > +
> > +	writel(MTK_NOR_WR_BUF_DISABLE, mt8173_nor->base + MTK_NOR_CFG2_REG);
> > +	ret =  readb_poll_timeout(mt8173_nor->base + MTK_NOR_CFG2_REG, reg,
> > +				  MTK_NOR_WR_BUF_DISABLE == (reg & 0xf), 100,
> > +				  10000);
> > +	if (ret)
> > +		dev_err(mt8173_nor->dev, "compare timeout!\n");
> > +	return ret;
> > +}
> > +
> > +static int mt8173_nor_erase_sector(struct spi_nor *nor, loff_t offset)
> > +{
> > +	struct mt8173_nor *mt8173_nor = nor->priv;
> > +
> > +	if (mt8173_nor_set_cmd(mt8173_nor, 0, 8, SPINOR_OP_WREN)) {
> > +		dev_err(mt8173_nor->dev,
> > +			"write enable failed in erase sector!\n");
> > +		return -EINVAL;
> > +	}
> > +
> > +	mt8173_nor_set_cmd(mt8173_nor, (int)offset, 32, SPINOR_OP_BE_4K);
> > +	return 0;
> > +}
> > +
> > +static int mt8173_nor_read_hw(struct mt8173_nor *mt8173_nor, int addr, int len,
> > +			      int *retlen, u8 *buf)
> > +{
> > +	int ret = 0, i;
> > +
> > +	mt8173_nor_set_read_mode(mt8173_nor);
> > +	writeb(HiByte(HiWord(addr)), mt8173_nor->base + MTK_NOR_RADR3_REG);
> > +	writeb(LoByte(HiWord(addr)), mt8173_nor->base + MTK_NOR_RADR2_REG);
> > +	writeb(HiByte(LoWord(addr)), mt8173_nor->base + MTK_NOR_RADR1_REG);
> > +	writeb(LoByte(LoWord(addr)), mt8173_nor->base + MTK_NOR_RADR0_REG);
> > +
> > +	for (i = 0; i < len; i++, (*retlen)++) {
> > +		if (mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_PIO_READ_CMD)) {
> > +			dev_err(mt8173_nor->dev, "read flash failed!\n");
> > +			return -EINVAL;
> > +		}
> > +		buf[i] = readb(mt8173_nor->base + MTK_NOR_RDATA_REG);
> > +	}
> > +	return ret;
> 
> ret will always be 0 here, drop the ret variable.
OK, I will drop the ret variable!
> 
> > +}
> > +
> > +static int mt8173_nor_read(struct spi_nor *nor, loff_t from, size_t len,
> > +			   size_t *retlen, u_char *buf)
> > +{
> > +	struct mt8173_nor *mt8173_nor = nor->priv;
> > +
> > +	return mt8173_nor_read_hw(mt8173_nor, (int)from, (int)len,
> > +				 (int *)retlen, (u8 *)buf);
> 
> mt8173_nor_read_hw is used only once here, no need for a separate
> function.
OK, I will remove the mt8173_nor_read_hw
> 
> > +}
> > +
> > +static int mt8173_nor_write_single_byte(struct mt8173_nor *mt8173_nor,
> > +					int u4addr, u8 u1data)
> > +{
> > +	if (u4addr >= mt8173_nor->mtd.size) {
> > +		dev_err(mt8173_nor->dev, "invalid write address!\n");
> > +		return -EINVAL;
> > +	}
> > +
> > +	writeb(u1data, mt8173_nor->base + MTK_NOR_WDATA_REG);
> > +	writeb(LoByte(HiWord(u4addr)), mt8173_nor->base + MTK_NOR_RADR2_REG);
> > +	writeb(HiByte(LoWord(u4addr)), mt8173_nor->base + MTK_NOR_RADR1_REG);
> > +	writeb(LoByte(LoWord(u4addr)), mt8173_nor->base + MTK_NOR_RADR0_REG);
> > +
> > +	if (mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_WR_CMD)) {
> > +		dev_err(mt8173_nor->dev, "write byte offset%08x\n", u4addr);
> > +		return -EINVAL;
> > +	}
> > +	return 0;
> > +}
> > +
> > +static int mt8173_nor_write_buffer(struct mt8173_nor *mt8173_nor, int u4addr,
> > +				   int u4len, const u8 *buf)
> > +{
> > +	int i, j, bufidx, data;
> > +
> > +	if (!buf)
> > +		return -EINVAL;
> > +
> > +	writeb(LoByte(HiWord(u4addr)), mt8173_nor->base + MTK_NOR_RADR2_REG);
> > +	writeb(HiByte(LoWord(u4addr)), mt8173_nor->base + MTK_NOR_RADR1_REG);
> > +	writeb(LoByte(LoWord(u4addr)), mt8173_nor->base + MTK_NOR_RADR0_REG);
> > +
> > +	bufidx = 0;
> > +	for (i = 0; i < u4len; i += 4) {
> > +		for (j = 0; j < 4; j++) {
> > +			(*((u8 *)&data + j)) = buf[bufidx];
> > +			bufidx++;
> > +		}
> > +		writel(data, mt8173_nor->base + MTK_NOR_PP_DATA_REG);
> > +	}
> > +
> > +	if (mt8173_nor_execute_cmd(mt8173_nor, MTK_NOR_WR_CMD)) {
> > +		dev_err(mt8173_nor->dev, "write buffer offset:%08x\n", u4addr);
> > +		return -EINVAL;
> > +	}
> > +	return 0;
> > +}
> > +
> > +static void mt8173_nor_write(struct spi_nor *nor, loff_t to, size_t len,
> > +			     size_t *retlen, const u_char *buf)
> > +{
> > +	struct mt8173_nor *mt8173_nor = nor->priv;
> > +	size_t i;
> > +
> > +	if (nor->page_size == len) {
> > +		if (mt8173_nor_write_buffer_enable(mt8173_nor))
> > +			dev_err(mt8173_nor->dev, "write buffer enable failed !\n");
> > +		while (len > 0) {
> > +			mt8173_nor_write_buffer(mt8173_nor, to,
> > +						SFLASH_WRBUF_SIZE, buf);
> > +			len -= SFLASH_WRBUF_SIZE;
> > +			to += SFLASH_WRBUF_SIZE;
> > +			buf += SFLASH_WRBUF_SIZE;
> > +			(*retlen) += SFLASH_WRBUF_SIZE;
> > +		}
> > +		if (mt8173_nor_write_buffer_disable(mt8173_nor))
> > +			dev_err(mt8173_nor->dev, "write buffer disable failed !\n");
> > +	} else {
> > +		for (i = 0; i < len; i++,  (*retlen)++) {
> > +			if (mt8173_nor_write_single_byte(mt8173_nor, to, *buf))
> > +				dev_err(mt8173_nor->dev, "write byte failed !\n");
> > +			to++;
> > +			buf++;
> > +		}
> > +	}
> > +}
> 
> Instead of using the buffer write method only for page_size sized writes
> I would expect a behaviour of this function like:
> 
> 	while (len > SFLASH_WRBUF_SIZE) {
> 		write_buffer();
> 		len -= SFLASH_WRBUF_SIZE;
> 	}
> 
> 	while (len) {
> 		write_single_byte();
> 		len--;
> 	}
> 
OK, I will use this method, Thanks for your instruct !
> > +
> > +static int mt8173_nor_read_reg(struct spi_nor *nor, u8 opcode, u8 *buf, int len)
> > +{
> > +	int ret = 0;
> > +	struct mt8173_nor *mt8173_nor = nor->priv;
> > +	/* mtk nor controller haven't supoort SPINOR_OP_RDCR */
> > +	if (opcode == SPINOR_OP_RDID || opcode == SPINOR_OP_RDSR)
> > +		ret = mt8173_nor_get_para(mt8173_nor, buf, len);
> > +	else
> > +		dev_warn(mt8173_nor->dev, "invalid cmd %d\n", opcode);
> > +
> > +	return ret;
> > +}
> > +
> > +static int mt8173_nor_write_reg(struct spi_nor *nor, u8 opcode, u8 *buf,
> > +				int len, int write_enable)
> > +{
> > +	int ret, cmd_to_nor, cmd_to_controller;
> > +	struct mt8173_nor *mt8173_nor = nor->priv;
> > +
> > +	if (opcode == SPINOR_OP_WRSR || opcode == SPINOR_OP_CHIP_ERASE) {
> > +		if (len > 0) {
> > +			cmd_to_nor = *buf;
> > +			cmd_to_controller = MTK_NOR_WRSR_CMD;
> > +		} else {
> > +			cmd_to_nor = opcode;
> > +			cmd_to_controller = MTK_NOR_PRG_CMD;
> > +		}
> > +		ret = mt8173_nor_set_para(mt8173_nor, cmd_to_nor,
> > +					  cmd_to_controller);
> > +	} else if (opcode == SPINOR_OP_WREN || opcode == SPINOR_OP_WRDI) {
> > +		ret = mt8173_nor_set_cmd(mt8173_nor, 0, 8, opcode);
> > +	} else {
> > +		dev_warn(mt8173_nor->dev, "have not support cmd %d\n", opcode);
> > +		ret = -EINVAL;
> > +	}
> > +	return ret;
> > +}
> > +
> > +static int __init mtk_nor_init(struct mt8173_nor *mt8173_nor,
> > +			       struct mtd_part_parser_data ppdata)
> 
> Why a copy and not a pointer to struct mtd_part_parser_data?
You are right, it seems a pointer will be more suitable
> 
> > +{
> > +	int ret;
> > +	struct spi_nor *nor;
> > +	struct mtd_info *mtd;
> > +
> > +	writel(MTK_NOR_ENABLE_SF_CMD, mt8173_nor->base + MTK_NOR_WRPROT_REG);
> > +	nor = &mt8173_nor->nor;
> > +	mtd = &mt8173_nor->mtd;
> > +	nor->mtd = mt8173_nor->mtd;
> > +	nor->dev = mt8173_nor->dev;
> > +	nor->priv = mt8173_nor;
> > +	mtd->priv = nor;
> > +
> > +	/* fill the hooks to spi nor */
> > +	nor->read = mt8173_nor_read;
> > +	nor->read_reg = mt8173_nor_read_reg;
> > +	nor->write = mt8173_nor_write;
> > +	nor->write_reg = mt8173_nor_write_reg;
> > +	nor->erase = mt8173_nor_erase_sector;
> > +	nor->mtd.owner = THIS_MODULE;
> > +	nor->mtd.name = "mtk_nor";
> > +	/* initialized with NULL */
> > +	ret = spi_nor_scan(nor, NULL, SPI_NOR_DUAL);
> > +	if (ret) {
> > +		dev_err(mt8173_nor->dev, "spi_nor_scan failed !\n");
> > +		return -EINVAL;
> 
> Just forward the error from spi_nor_scan.
Ok, I will fixed it !
> 
> > +	}
> > +	dev_dbg(mt8173_nor->dev, "mtd->size :0x%llx!\n", mtd->size);
> > +	ret = mtd_device_parse_register(&nor->mtd, NULL, &ppdata, NULL, 0);
> > +
> > +	return ret;
> > +}
> > +
> > +static int mtk_nor_drv_probe(struct platform_device *pdev)
> > +{
> > +	struct device_node *np = pdev->dev.of_node;
> > +	struct mtd_part_parser_data ppdata;
> > +	struct resource *res;
> > +	int ret;
> > +	struct mt8173_nor *mt8173_nor = devm_kzalloc(&pdev->dev,
> > +		sizeof(*mt8173_nor), GFP_KERNEL);
> > +
> > +	if (!pdev->dev.of_node) {
> > +		dev_err(&pdev->dev, "No DT found\n");
> > +		return -EINVAL;
> > +	}
> > +
> > +	if (!mt8173_nor)
> > +		return -ENOMEM;
> > +	platform_set_drvdata(pdev, mt8173_nor);
> > +
> > +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > +	mt8173_nor->base = devm_ioremap_resource(&pdev->dev, res);
> > +	if (IS_ERR(mt8173_nor->base)) {
> > +		ret = PTR_ERR(mt8173_nor->base);
> > +		goto nor_free;
> > +	}
> > +
> > +	mt8173_nor->spi_clk = devm_clk_get(&pdev->dev, "spi_clk");
> > +	if (IS_ERR(mt8173_nor->spi_clk)) {
> > +		ret = PTR_ERR(mt8173_nor->spi_clk);
> > +		goto nor_free;
> > +	}
> > +
> > +	mt8173_nor->src_axi_clk = devm_clk_get(&pdev->dev, "axi_clk");
> > +	if (IS_ERR(mt8173_nor->src_axi_clk)) {
> > +		ret = PTR_ERR(mt8173_nor->src_axi_clk);
> > +		goto nor_free;
> > +	}
> > +
> > +	mt8173_nor->sf_mux_clk = devm_clk_get(&pdev->dev, "mux_clk");
> > +	if (IS_ERR(mt8173_nor->sf_mux_clk)) {
> > +		ret = PTR_ERR(mt8173_nor->sf_mux_clk);
> > +		goto nor_free;
> > +	}
> > +
> > +	mt8173_nor->nor_clk = devm_clk_get(&pdev->dev, "sf_clk");
> > +	if (IS_ERR(mt8173_nor->nor_clk)) {
> > +		ret = PTR_ERR(mt8173_nor->nor_clk);
> > +		goto nor_free;
> > +	}
> > +
> > +	mt8173_nor->dev = &pdev->dev;
> > +	clk_prepare_enable(mt8173_nor->spi_clk);
> > +	clk_prepare_enable(mt8173_nor->src_axi_clk);
> > +	clk_prepare_enable(mt8173_nor->sf_mux_clk);
> > +	clk_prepare_enable(mt8173_nor->nor_clk);
> > +	clk_set_parent(mt8173_nor->nor_clk, mt8173_nor->sf_mux_clk);
> 
> sf_mux_clk is inherently enabled when you enable one of its child
> clocks, like nor_clk in this case, so you don't have to enable it
> explicitly.
> Also putting knowledge of the SoCs clock layout into the driver is a bad
> idea. There is the assigned-clock-parents binding which you can use here
> for assigning the clock parent.
Ok. I will not to enable the parent clock here.

> 
> > +
> > +	ppdata.of_node = np;
> > +	ret = mtk_nor_init(mt8173_nor, ppdata);
> > +
> > +nor_free:
> > +	return ret;
> > +}
> > +
> > +static int mtk_nor_drv_remove(struct platform_device *pdev)
> > +{
> > +	struct mt8173_nor *mt8173_nor = platform_get_drvdata(pdev);
> > +
> > +	clk_disable_unprepare(mt8173_nor->spi_clk);
> > +	clk_disable_unprepare(mt8173_nor->src_axi_clk);
> > +	clk_disable_unprepare(mt8173_nor->sf_mux_clk);
> > +	clk_disable_unprepare(mt8173_nor->nor_clk);
> > +	mtd_device_unregister(&mt8173_nor->mtd);
> 
> This order is wrong. You should not disable clocks on a device that
> might be active. You should unregister it first and disable the clocks
> afterwards.

OK , I will change the order, and Thanks for your instruct again ! 
> 
> Sascha
> 
> 

[PATCH 3/3] arm64: dts: mt8173: Add nor flash node

[Bayi Cheng]

Add Mediatek nor flash node

Signed-off-by: Bayi Cheng <bayi.cheng@mediatek.com>
---
 arch/arm64/boot/dts/mediatek/mt8173.dtsi | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/arch/arm64/boot/dts/mediatek/mt8173.dtsi b/arch/arm64/boot/dts/mediatek/mt8173.dtsi
index d18ee42..a14f005 100644
--- a/arch/arm64/boot/dts/mediatek/mt8173.dtsi
+++ b/arch/arm64/boot/dts/mediatek/mt8173.dtsi
@@ -365,6 +365,16 @@
 			status = "disabled";
 		};
 
+		nor_flash: nor at 1100d000 {
+			compatible = "mediatek,mt8173-nor";
+			reg = <0 0x1100d000 0 0xe0>;
+			clocks = <&pericfg CLK_PERI_SPI>,
+				 <&topckgen CLK_TOP_AXI_SEL>,
+				 <&topckgen CLK_TOP_UNIVPLL2_D8>,
+				 <&topckgen CLK_TOP_SPINFI_IFR_SEL>;
+			clock-names = "spi_clk", "axi_clk", "mux_clk", "sf_clk";
+		};
+
 		i2c3: i2c3 at 11010000 {
 			compatible = "mediatek,mt8173-i2c";
 			reg = <0 0x11010000 0 0x70>,
-- 
1.8.1.1.dirty

[PATCH 3/3] arm64: dts: mt8173: Add nor flash node

[Jagan Teki]

On 8 September 2015 at 15:19, Bayi Cheng <bayi.cheng@mediatek.com> wrote:
> Add Mediatek nor flash node
>
> Signed-off-by: Bayi Cheng <bayi.cheng@mediatek.com>
> ---
>  arch/arm64/boot/dts/mediatek/mt8173.dtsi | 10 ++++++++++
>  1 file changed, 10 insertions(+)
>
> diff --git a/arch/arm64/boot/dts/mediatek/mt8173.dtsi b/arch/arm64/boot/dts/mediatek/mt8173.dtsi
> index d18ee42..a14f005 100644
> --- a/arch/arm64/boot/dts/mediatek/mt8173.dtsi
> +++ b/arch/arm64/boot/dts/mediatek/mt8173.dtsi
> @@ -365,6 +365,16 @@
>                         status = "disabled";
>                 };
>
> +               nor_flash: nor at 1100d000 {

Based on the comments from 1/3 - this notation needs to be change something like
qspi0: quadspi at 1100d000

> +                       compatible = "mediatek,mt8173-nor";
> +                       reg = <0 0x1100d000 0 0xe0>;
> +                       clocks = <&pericfg CLK_PERI_SPI>,
> +                                <&topckgen CLK_TOP_AXI_SEL>,
> +                                <&topckgen CLK_TOP_UNIVPLL2_D8>,
> +                                <&topckgen CLK_TOP_SPINFI_IFR_SEL>;
> +                       clock-names = "spi_clk", "axi_clk", "mux_clk", "sf_clk";
> +               };
> +
>                 i2c3: i2c3 at 11010000 {
>                         compatible = "mediatek,mt8173-i2c";
>                         reg = <0 0x11010000 0 0x70>,
> --
> 1.8.1.1.dirty
>

thanks!
-- 
Jagan | openedev.



Sent with MailTrack

[PATCH 3/3] arm64: dts: mt8173: Add nor flash node

[Ezequiel Garcia]

On 8 September 2015 at 08:53, Jagan Teki <jteki@openedev.com> wrote:
> On 8 September 2015 at 15:19, Bayi Cheng <bayi.cheng@mediatek.com> wrote:
>> Add Mediatek nor flash node
>>
>> Signed-off-by: Bayi Cheng <bayi.cheng@mediatek.com>
>> ---
>>  arch/arm64/boot/dts/mediatek/mt8173.dtsi | 10 ++++++++++
>>  1 file changed, 10 insertions(+)
>>
>> diff --git a/arch/arm64/boot/dts/mediatek/mt8173.dtsi b/arch/arm64/boot/dts/mediatek/mt8173.dtsi
>> index d18ee42..a14f005 100644
>> --- a/arch/arm64/boot/dts/mediatek/mt8173.dtsi
>> +++ b/arch/arm64/boot/dts/mediatek/mt8173.dtsi
>> @@ -365,6 +365,16 @@
>>                         status = "disabled";
>>                 };
>>
>> +               nor_flash: nor at 1100d000 {
>
> Based on the comments from 1/3 - this notation needs to be change something like
> qspi0: quadspi at 1100d000
>

Actually, to follow ePAPR recomendations it should be named as flash at 1100d000.
(See ePAPR, 2.2.2 Generic Names Recommendation).

I believe the phandle name choice can be more descriptive.
-- 
Ezequiel Garc?a, VanguardiaSur
www.vanguardiasur.com.ar

[PATCH 3/3] arm64: dts: mt8173: Add nor flash node

[Rob Herring]

On 09/08/2015 10:18 AM, Ezequiel Garcia wrote:
> On 8 September 2015 at 08:53, Jagan Teki <jteki@openedev.com> wrote:
>> On 8 September 2015 at 15:19, Bayi Cheng <bayi.cheng@mediatek.com> wrote:
>>> Add Mediatek nor flash node
>>>
>>> Signed-off-by: Bayi Cheng <bayi.cheng@mediatek.com>
>>> ---
>>>  arch/arm64/boot/dts/mediatek/mt8173.dtsi | 10 ++++++++++
>>>  1 file changed, 10 insertions(+)
>>>
>>> diff --git a/arch/arm64/boot/dts/mediatek/mt8173.dtsi b/arch/arm64/boot/dts/mediatek/mt8173.dtsi
>>> index d18ee42..a14f005 100644
>>> --- a/arch/arm64/boot/dts/mediatek/mt8173.dtsi
>>> +++ b/arch/arm64/boot/dts/mediatek/mt8173.dtsi
>>> @@ -365,6 +365,16 @@
>>>                         status = "disabled";
>>>                 };
>>>
>>> +               nor_flash: nor at 1100d000 {
>>
>> Based on the comments from 1/3 - this notation needs to be change something like
>> qspi0: quadspi at 1100d000
>>
> 
> Actually, to follow ePAPR recomendations it should be named as flash at 1100d000.
> (See ePAPR, 2.2.2 Generic Names Recommendation).

The flash device node should, but this is the controller which should be
"spi" IMO even if this is not a general purpose controller.

Rob

[PATCH 3/3] arm64: dts: mt8173: Add nor flash node

[bayi.cheng]

On Tue, 2015-09-08 at 18:46 -0500, Rob Herring wrote:
> On 09/08/2015 10:18 AM, Ezequiel Garcia wrote:
> > On 8 September 2015 at 08:53, Jagan Teki <jteki@openedev.com> wrote:
> >> On 8 September 2015 at 15:19, Bayi Cheng <bayi.cheng@mediatek.com> wrote:
> >>> Add Mediatek nor flash node
> >>>
> >>> Signed-off-by: Bayi Cheng <bayi.cheng@mediatek.com>
> >>> ---
> >>>  arch/arm64/boot/dts/mediatek/mt8173.dtsi | 10 ++++++++++
> >>>  1 file changed, 10 insertions(+)
> >>>
> >>> diff --git a/arch/arm64/boot/dts/mediatek/mt8173.dtsi b/arch/arm64/boot/dts/mediatek/mt8173.dtsi
> >>> index d18ee42..a14f005 100644
> >>> --- a/arch/arm64/boot/dts/mediatek/mt8173.dtsi
> >>> +++ b/arch/arm64/boot/dts/mediatek/mt8173.dtsi
> >>> @@ -365,6 +365,16 @@
> >>>                         status = "disabled";
> >>>                 };
> >>>
> >>> +               nor_flash: nor at 1100d000 {
> >>
> >> Based on the comments from 1/3 - this notation needs to be change something like
> >> qspi0: quadspi at 1100d000
> >>
> > 
> > Actually, to follow ePAPR recomendations it should be named as flash at 1100d000.
> > (See ePAPR, 2.2.2 Generic Names Recommendation).
> 
> The flash device node should, but this is the controller which should be
> "spi" IMO even if this is not a general purpose controller.
> 
> Rob
> 
HI Rob, Thanks for your instruct! I will fix it !

[PATCH 3/3] arm64: dts: mt8173: Add nor flash node

[Brian Norris]

On Fri, Sep 11, 2015 at 05:51:16PM +0800, bayi.cheng wrote:
> On Tue, 2015-09-08 at 18:46 -0500, Rob Herring wrote:
> > On 09/08/2015 10:18 AM, Ezequiel Garcia wrote:
> > > On 8 September 2015 at 08:53, Jagan Teki <jteki@openedev.com> wrote:
> > >> On 8 September 2015 at 15:19, Bayi Cheng <bayi.cheng@mediatek.com> wrote:
> > >>> Add Mediatek nor flash node
> > >>>
> > >>> Signed-off-by: Bayi Cheng <bayi.cheng@mediatek.com>
> > >>> ---
> > >>>  arch/arm64/boot/dts/mediatek/mt8173.dtsi | 10 ++++++++++
> > >>>  1 file changed, 10 insertions(+)
> > >>>
> > >>> diff --git a/arch/arm64/boot/dts/mediatek/mt8173.dtsi b/arch/arm64/boot/dts/mediatek/mt8173.dtsi
> > >>> index d18ee42..a14f005 100644
> > >>> --- a/arch/arm64/boot/dts/mediatek/mt8173.dtsi
> > >>> +++ b/arch/arm64/boot/dts/mediatek/mt8173.dtsi
> > >>> @@ -365,6 +365,16 @@
> > >>>                         status = "disabled";
> > >>>                 };
> > >>>
> > >>> +               nor_flash: nor at 1100d000 {
> > >>
> > >> Based on the comments from 1/3 - this notation needs to be change something like
> > >> qspi0: quadspi at 1100d000
> > >>
> > > 
> > > Actually, to follow ePAPR recomendations it should be named as flash at 1100d000.
> > > (See ePAPR, 2.2.2 Generic Names Recommendation).
> > 
> > The flash device node should, but this is the controller which should be
> > "spi" IMO even if this is not a general purpose controller.
> > 
> > Rob
> > 
> HI Rob, Thanks for your instruct! I will fix it !

OK, so given there are several cooks in the kitchen, and I just read
these replies after replying independently to the binding doc, I'll try
to summarize the consensus, flavored with my own opinion:

 * the node name should not be 'nor'; it should be something more along
   the lines of ePAPR. So 'flash' or 'spi'
 * the phandle name is less important, and can be more descriptive
 * there should be a subnode to represent the flash separately from the
   controller

So we might put this together to:

	whatever_name_you_like: spi at 1100d000 {
		...
		flash at 0 {
			...
		};
	};

Brian

[PATCH 3/3] arm64: dts: mt8173: Add nor flash node

[bayi.cheng]

On Tue, 2015-09-08 at 12:18 -0300, Ezequiel Garcia wrote:
> On 8 September 2015 at 08:53, Jagan Teki <jteki@openedev.com> wrote:
> > On 8 September 2015 at 15:19, Bayi Cheng <bayi.cheng@mediatek.com> wrote:
> >> Add Mediatek nor flash node
> >>
> >> Signed-off-by: Bayi Cheng <bayi.cheng@mediatek.com>
> >> ---
> >>  arch/arm64/boot/dts/mediatek/mt8173.dtsi | 10 ++++++++++
> >>  1 file changed, 10 insertions(+)
> >>
> >> diff --git a/arch/arm64/boot/dts/mediatek/mt8173.dtsi b/arch/arm64/boot/dts/mediatek/mt8173.dtsi
> >> index d18ee42..a14f005 100644
> >> --- a/arch/arm64/boot/dts/mediatek/mt8173.dtsi
> >> +++ b/arch/arm64/boot/dts/mediatek/mt8173.dtsi
> >> @@ -365,6 +365,16 @@
> >>                         status = "disabled";
> >>                 };
> >>
> >> +               nor_flash: nor at 1100d000 {
> >
> > Based on the comments from 1/3 - this notation needs to be change something like
> > qspi0: quadspi at 1100d000
> >
> 
> Actually, to follow ePAPR recomendations it should be named as flash at 1100d000.
> (See ePAPR, 2.2.2 Generic Names Recommendation).
> 
> I believe the phandle name choice can be more descriptive.

Thanks for your instruct, I will fix it in the next patch ! 

[PATCH 3/3] arm64: dts: mt8173: Add nor flash node

[bayi.cheng]

On Tue, 2015-09-08 at 17:23 +0530, Jagan Teki wrote:
> On 8 September 2015 at 15:19, Bayi Cheng <bayi.cheng@mediatek.com> wrote:
> > Add Mediatek nor flash node
> >
> > Signed-off-by: Bayi Cheng <bayi.cheng@mediatek.com>
> > ---
> >  arch/arm64/boot/dts/mediatek/mt8173.dtsi | 10 ++++++++++
> >  1 file changed, 10 insertions(+)
> >
> > diff --git a/arch/arm64/boot/dts/mediatek/mt8173.dtsi b/arch/arm64/boot/dts/mediatek/mt8173.dtsi
> > index d18ee42..a14f005 100644
> > --- a/arch/arm64/boot/dts/mediatek/mt8173.dtsi
> > +++ b/arch/arm64/boot/dts/mediatek/mt8173.dtsi
> > @@ -365,6 +365,16 @@
> >                         status = "disabled";
> >                 };
> >
> > +               nor_flash: nor at 1100d000 {
> 
> Based on the comments from 1/3 - this notation needs to be change something like
> qspi0: quadspi at 1100d000

OK, I will fixed it!
> 
> > +                       compatible = "mediatek,mt8173-nor";
> > +                       reg = <0 0x1100d000 0 0xe0>;
> > +                       clocks = <&pericfg CLK_PERI_SPI>,
> > +                                <&topckgen CLK_TOP_AXI_SEL>,
> > +                                <&topckgen CLK_TOP_UNIVPLL2_D8>,
> > +                                <&topckgen CLK_TOP_SPINFI_IFR_SEL>;
> > +                       clock-names = "spi_clk", "axi_clk", "mux_clk", "sf_clk";
> > +               };
> > +
> >                 i2c3: i2c3 at 11010000 {
> >                         compatible = "mediatek,mt8173-i2c";
> >                         reg = <0 0x11010000 0 0x70>,
> > --
> > 1.8.1.1.dirty
> >
> 
> thanks!