[PATCH] Update Nanobone

[PATCH] Update Nanobone

[Mark Jackson]

Update Nanobone DTS file as follows:-
- Add USB hooks
- Fix GPIO settings for RTS/CTS pins
- Add LM75 hooks
- Fix GPIO settings for MMC pins

Add nanobone_defconfig file.
---
 arch/arm/boot/dts/am335x-nano.dts   |  58 ++++++--
 arch/arm/configs/nanobone_defconfig | 222 ++++++++++++++++++++++++++++
 2 files changed, 268 insertions(+), 12 deletions(-)
 create mode 100644 arch/arm/configs/nanobone_defconfig

diff --git a/arch/arm/boot/dts/am335x-nano.dts b/arch/arm/boot/dts/am335x-nano.dts
index b6f2567bd65a..e387a7b5de9b 100644
--- a/arch/arm/boot/dts/am335x-nano.dts
+++ b/arch/arm/boot/dts/am335x-nano.dts
@@ -102,8 +102,8 @@ AM33XX_PADCONF(AM335X_PIN_UART0_TXD, PIN_OUTPUT, MUX_MODE0)
 
 	uart1_pins: uart1_pins {
 		pinctrl-single,pins = <
-			AM33XX_PADCONF(AM335X_PIN_UART1_CTSN, PIN_OUTPUT, MUX_MODE7)
-			AM33XX_PADCONF(AM335X_PIN_UART1_RTSN, PIN_OUTPUT, MUX_MODE7)
+			AM33XX_PADCONF(AM335X_PIN_UART1_CTSN, PIN_OUTPUT, MUX_MODE7)		/* uart1_ctsn.gpio0[12] */
+			AM33XX_PADCONF(AM335X_PIN_UART1_RTSN, PIN_OUTPUT, MUX_MODE7)		/* uart1_rtsn.gpio0[13] */
 			AM33XX_PADCONF(AM335X_PIN_UART1_RXD, PIN_INPUT_PULLUP, MUX_MODE0)
 			AM33XX_PADCONF(AM335X_PIN_UART1_TXD, PIN_OUTPUT, MUX_MODE0)
 		>;
@@ -120,17 +120,17 @@ AM33XX_PADCONF(AM335X_PIN_SPI0_D0, PIN_OUTPUT, MUX_MODE1)		/* spi0_d0.uart2_txd
 
 	uart3_pins: uart3_pins {
 		pinctrl-single,pins = <
-			AM33XX_PADCONF(AM335X_PIN_LCD_DATA10, PIN_INPUT_PULLUP, MUX_MODE6)	/* lcd_data10.uart3_ctsn */
-			AM33XX_PADCONF(AM335X_PIN_LCD_DATA11, PIN_OUTPUT, MUX_MODE6)		/* lcd_data11.uart3_rtsn */
+			AM33XX_PADCONF(AM335X_PIN_LCD_DATA10, PIN_INPUT_PULLUP, MUX_MODE7)	/* lcd_data10.gpio2[16] */
+			AM33XX_PADCONF(AM335X_PIN_LCD_DATA11, PIN_OUTPUT, MUX_MODE7)		/* lcd_data11.gpio2[17] */
 			AM33XX_PADCONF(AM335X_PIN_SPI0_CS1, PIN_INPUT, MUX_MODE1)		/* spi0_cs1.uart3_rxd */
-			AM33XX_PADCONF(AM335X_PIN_ECAP0_IN_PWM0_OUT, PIN_OUTPUT, MUX_MODE1)		/* ecap0_in_pwm0_out.uart3_txd */
+			AM33XX_PADCONF(AM335X_PIN_ECAP0_IN_PWM0_OUT, PIN_OUTPUT, MUX_MODE1)	/* ecap0_in_pwm0_out.uart3_txd */
 		>;
 	};
 
 	uart4_pins: uart4_pins {
 		pinctrl-single,pins = <
-			AM33XX_PADCONF(AM335X_PIN_LCD_DATA12, PIN_INPUT_PULLUP, MUX_MODE6)	/* lcd_data12.uart4_ctsn */
-			AM33XX_PADCONF(AM335X_PIN_LCD_DATA13, PIN_OUTPUT, MUX_MODE6)		/* lcd_data13.uart4_rtsn */
+			AM33XX_PADCONF(AM335X_PIN_LCD_DATA12, PIN_INPUT_PULLUP, MUX_MODE7)	/* lcd_data12.gpio0[8] */
+			AM33XX_PADCONF(AM335X_PIN_LCD_DATA13, PIN_OUTPUT, MUX_MODE7)		/* lcd_data13.gpio0[9] */
 			AM33XX_PADCONF(AM335X_PIN_UART0_CTSN, PIN_INPUT, MUX_MODE1)		/* uart0_ctsn.uart4_rxd */
 			AM33XX_PADCONF(AM335X_PIN_UART0_RTSN, PIN_OUTPUT, MUX_MODE1)		/* uart0_rtsn.uart4_txd */
 		>;
@@ -149,9 +149,9 @@ AM33XX_PADCONF(AM335X_PIN_MMC0_DAT3, PIN_INPUT_PULLUP, MUX_MODE0)
 			AM33XX_PADCONF(AM335X_PIN_MMC0_DAT2, PIN_INPUT_PULLUP, MUX_MODE0)
 			AM33XX_PADCONF(AM335X_PIN_MMC0_DAT1, PIN_INPUT_PULLUP, MUX_MODE0)
 			AM33XX_PADCONF(AM335X_PIN_MMC0_DAT0, PIN_INPUT_PULLUP, MUX_MODE0)
-			AM33XX_PADCONF(AM335X_PIN_MMC0_CLK, PIN_INPUT_PULLUP, MUX_MODE0)	/* mmc0_clk.mmc0_clk */
-			AM33XX_PADCONF(AM335X_PIN_MMC0_CMD, PIN_INPUT_PULLUP, MUX_MODE0)	/* mmc0_cmd.mmc0_cmd */
-			AM33XX_PADCONF(AM335X_PIN_EMU1, PIN_INPUT_PULLUP, MUX_MODE7)	/* emu1.gpio3[8] */
+			AM33XX_PADCONF(AM335X_PIN_MMC0_CLK, PIN_INPUT_PULLUP, MUX_MODE0)
+			AM33XX_PADCONF(AM335X_PIN_MMC0_CMD, PIN_INPUT_PULLUP, MUX_MODE0)
+			AM33XX_PADCONF(AM335X_PIN_EMU1, PIN_INPUT_PULLUP, MUX_MODE7)		/* emu1.gpio3[8] */
 			AM33XX_PADCONF(AM335X_PIN_MCASP0_ACLKR, PIN_INPUT_PULLUP, MUX_MODE7)	/* mcasp0_aclkr.gpio3[18] */
 		>;
 	};
@@ -188,12 +188,22 @@ &uart3 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&uart3_pins>;
 	status = "okay";
+	rts-gpio = <&gpio2 17 GPIO_ACTIVE_HIGH>;
+	rs485-rts-active-high;
+	rs485-rx-during-tx;
+	rs485-rts-delay = <1 1>;
+	linux,rs485-enabled-at-boot-time;
 };
 
 &uart4 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&uart4_pins>;
 	status = "okay";
+	rts-gpio = <&gpio0 9 GPIO_ACTIVE_HIGH>;
+	rs485-rts-active-high;
+	rs485-rx-during-tx;
+	rs485-rts-delay = <1 1>;
+	linux,rs485-enabled-at-boot-time;
 };
 
 &uart5 {
@@ -220,6 +230,12 @@ tps: tps@24 {
 		reg = <0x24>;
 	};
 
+	lm75@48 {
+		compatible = "lm75";
+		reg = <0x48>;
+		status = "okay";
+	};
+
 	eeprom@53 {
 		compatible = "microchip,24c02", "atmel,24c02";
 		reg = <0x53>;
@@ -403,8 +419,26 @@ &mmc1 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&mmc1_pins>;
 	bus-width = <4>;
-	cd-gpios = <&gpio3 8 0>;
-	wp-gpios = <&gpio3 18 0>;
+	cd-debounce-delay-ms = <5>;
+	cd-gpios = <&gpio3 8 GPIO_ACTIVE_LOW>;
+	wp-gpios = <&gpio3 18 GPIO_ACTIVE_HIGH>;
+};
+
+&usb {
+	status = "okay";
+};
+
+&usb_ctrl_mod {
+	status = "okay";
+};
+
+&usb0_phy {
+	status = "okay";
+};
+
+&usb0 {
+	status = "okay";
+	dr_mode = "host";
 };
 
 #include "tps65217.dtsi"
diff --git a/arch/arm/configs/nanobone_defconfig b/arch/arm/configs/nanobone_defconfig
new file mode 100644
index 000000000000..236ce7210013
--- /dev/null
+++ b/arch/arm/configs/nanobone_defconfig
@@ -0,0 +1,222 @@
+CONFIG_SYSVIPC=y
+CONFIG_POSIX_MQUEUE=y
+CONFIG_USELIB=y
+CONFIG_NO_HZ=y
+CONFIG_HIGH_RES_TIMERS=y
+CONFIG_BSD_PROCESS_ACCT=y
+CONFIG_IKCONFIG=y
+CONFIG_IKCONFIG_PROC=y
+CONFIG_LOG_BUF_SHIFT=16
+CONFIG_NAMESPACES=y
+CONFIG_BLK_DEV_INITRD=y
+# CONFIG_RD_BZIP2 is not set
+# CONFIG_RD_LZMA is not set
+# CONFIG_RD_XZ is not set
+# CONFIG_RD_LZO is not set
+# CONFIG_RD_LZ4 is not set
+# CONFIG_RD_ZSTD is not set
+CONFIG_EMBEDDED=y
+CONFIG_PERF_EVENTS=y
+CONFIG_ARCH_OMAP3=y
+CONFIG_SOC_AM33XX=y
+# CONFIG_SOC_OMAP3430 is not set
+CONFIG_ARM_THUMBEE=y
+CONFIG_PL310_ERRATA_588369=y
+CONFIG_PL310_ERRATA_727915=y
+CONFIG_ARM_ERRATA_720789=y
+CONFIG_ARM_ERRATA_814220=y
+CONFIG_HAVE_ARM_ARCH_TIMER=y
+CONFIG_OABI_COMPAT=y
+# CONFIG_CPU_SW_DOMAIN_PAN is not set
+CONFIG_ARM_APPENDED_DTB=y
+CONFIG_ARM_ATAG_DTB_COMPAT=y
+CONFIG_CMDLINE="root=/dev/mmcblk0p2 rootwait console=ttyO2,115200"
+CONFIG_KEXEC=y
+CONFIG_CPU_FREQ=y
+CONFIG_FPE_NWFPE=y
+# CONFIG_STACKPROTECTOR is not set
+# CONFIG_BLK_DEBUG_FS is not set
+CONFIG_PARTITION_ADVANCED=y
+# CONFIG_MQ_IOSCHED_KYBER is not set
+CONFIG_BINFMT_MISC=y
+CONFIG_SLAB=y
+CONFIG_NET=y
+CONFIG_PACKET=y
+CONFIG_UNIX=y
+CONFIG_XFRM_USER=y
+CONFIG_NET_KEY=y
+CONFIG_NET_KEY_MIGRATE=y
+CONFIG_INET=y
+CONFIG_IP_PNP=y
+CONFIG_IP_PNP_DHCP=y
+# CONFIG_INET_DIAG is not set
+# CONFIG_IPV6 is not set
+CONFIG_NET_SWITCHDEV=y
+# CONFIG_WIRELESS is not set
+# CONFIG_ETHTOOL_NETLINK is not set
+CONFIG_UEVENT_HELPER=y
+CONFIG_UEVENT_HELPER_PATH="/sbin/hotplug"
+CONFIG_DEVTMPFS=y
+CONFIG_DEVTMPFS_MOUNT=y
+# CONFIG_FW_CACHE is not set
+CONFIG_CONNECTOR=y
+CONFIG_MTD=y
+CONFIG_MTD_BLOCK=y
+CONFIG_MTD_CFI=y
+CONFIG_MTD_CFI_INTELEXT=y
+CONFIG_MTD_CFI_AMDSTD=y
+CONFIG_MTD_CFI_STAA=y
+CONFIG_MTD_PHYSMAP=y
+CONFIG_MTD_PHYSMAP_OF=y
+CONFIG_MTD_PLATRAM=y
+CONFIG_MTD_BLOCK2MTD=y
+CONFIG_MTD_UBI=y
+CONFIG_BLK_DEV_LOOP=y
+CONFIG_BLK_DEV_RAM=y
+CONFIG_BLK_DEV_RAM_SIZE=16384
+CONFIG_EEPROM_AT24=y
+CONFIG_NETDEVICES=y
+# CONFIG_NET_VENDOR_ALACRITECH is not set
+# CONFIG_NET_VENDOR_AMAZON is not set
+# CONFIG_NET_VENDOR_AQUANTIA is not set
+# CONFIG_NET_VENDOR_ARC is not set
+# CONFIG_NET_VENDOR_ASIX is not set
+# CONFIG_NET_VENDOR_BROADCOM is not set
+# CONFIG_NET_VENDOR_CADENCE is not set
+# CONFIG_NET_VENDOR_CAVIUM is not set
+# CONFIG_NET_VENDOR_CIRRUS is not set
+# CONFIG_NET_VENDOR_CORTINA is not set
+# CONFIG_NET_VENDOR_DAVICOM is not set
+# CONFIG_NET_VENDOR_ENGLEDER is not set
+# CONFIG_NET_VENDOR_EZCHIP is not set
+# CONFIG_NET_VENDOR_FARADAY is not set
+# CONFIG_NET_VENDOR_FUNGIBLE is not set
+# CONFIG_NET_VENDOR_GOOGLE is not set
+# CONFIG_NET_VENDOR_HISILICON is not set
+# CONFIG_NET_VENDOR_HUAWEI is not set
+# CONFIG_NET_VENDOR_INTEL is not set
+# CONFIG_NET_VENDOR_WANGXUN is not set
+# CONFIG_NET_VENDOR_LITEX is not set
+# CONFIG_NET_VENDOR_MARVELL is not set
+# CONFIG_NET_VENDOR_MELLANOX is not set
+# CONFIG_NET_VENDOR_MICREL is not set
+# CONFIG_NET_VENDOR_MICROCHIP is not set
+# CONFIG_NET_VENDOR_MICROSEMI is not set
+# CONFIG_NET_VENDOR_MICROSOFT is not set
+# CONFIG_NET_VENDOR_NI is not set
+# CONFIG_NET_VENDOR_NATSEMI is not set
+# CONFIG_NET_VENDOR_NETRONOME is not set
+# CONFIG_NET_VENDOR_PENSANDO is not set
+# CONFIG_NET_VENDOR_QUALCOMM is not set
+# CONFIG_NET_VENDOR_RENESAS is not set
+# CONFIG_NET_VENDOR_ROCKER is not set
+# CONFIG_NET_VENDOR_SAMSUNG is not set
+# CONFIG_NET_VENDOR_SEEQ is not set
+# CONFIG_NET_VENDOR_SOLARFLARE is not set
+# CONFIG_NET_VENDOR_SMSC is not set
+# CONFIG_NET_VENDOR_SOCIONEXT is not set
+# CONFIG_NET_VENDOR_STMICRO is not set
+# CONFIG_NET_VENDOR_SYNOPSYS is not set
+CONFIG_TI_CPSW=y
+CONFIG_TI_CPSW_SWITCHDEV=y
+# CONFIG_NET_VENDOR_VERTEXCOM is not set
+# CONFIG_NET_VENDOR_VIA is not set
+# CONFIG_NET_VENDOR_WIZNET is not set
+# CONFIG_NET_VENDOR_XILINX is not set
+CONFIG_SMSC_PHY=y
+# CONFIG_USB_NET_DRIVERS is not set
+# CONFIG_WLAN is not set
+# CONFIG_INPUT_LEDS is not set
+# CONFIG_INPUT_KEYBOARD is not set
+# CONFIG_INPUT_MOUSE is not set
+# CONFIG_SERIO is not set
+CONFIG_VT_HW_CONSOLE_BINDING=y
+# CONFIG_LEGACY_PTYS is not set
+# CONFIG_LDISC_AUTOLOAD is not set
+CONFIG_SERIAL_OMAP=y
+CONFIG_SERIAL_OMAP_CONSOLE=y
+# CONFIG_HW_RANDOM_OMAP3_ROM is not set
+CONFIG_I2C_CHARDEV=y
+# CONFIG_PTP_1588_CLOCK is not set
+CONFIG_PINCTRL_MCP23S08=y
+CONFIG_PINCTRL_SINGLE=y
+CONFIG_GPIO_SYSFS=y
+CONFIG_GPIO_GENERIC_PLATFORM=y
+CONFIG_POWER_RESET=y
+CONFIG_POWER_SUPPLY=y
+CONFIG_SENSORS_LM75=y
+CONFIG_WATCHDOG=y
+# CONFIG_WATCHDOG_HANDLE_BOOT_ENABLED is not set
+CONFIG_OMAP_WATCHDOG=y
+CONFIG_TWL4030_WATCHDOG=y
+CONFIG_MFD_TPS65217=y
+CONFIG_REGULATOR_TPS65217=y
+CONFIG_USB=y
+CONFIG_USB_ANNOUNCE_NEW_DEVICES=y
+CONFIG_USB_MON=y
+CONFIG_USB_MUSB_HDRC=y
+CONFIG_USB_MUSB_OMAP2PLUS=y
+CONFIG_USB_MUSB_DSPS=y
+CONFIG_USB_TI_CPPI41_DMA=y
+CONFIG_NOP_USB_XCEIV=y
+CONFIG_AM335X_PHY_USB=y
+CONFIG_MMC=y
+# CONFIG_PWRSEQ_EMMC is not set
+# CONFIG_PWRSEQ_SIMPLE is not set
+CONFIG_SDIO_UART=y
+CONFIG_MMC_DEBUG=y
+CONFIG_MMC_OMAP_HS=y
+CONFIG_NEW_LEDS=y
+CONFIG_LEDS_CLASS=y
+CONFIG_RTC_CLASS=y
+# CONFIG_RTC_NVMEM is not set
+CONFIG_RTC_DRV_DS1307=y
+CONFIG_DMADEVICES=y
+# CONFIG_VIRTIO_MENU is not set
+# CONFIG_VHOST_MENU is not set
+# CONFIG_COMMON_CLK_TI_ADPLL is not set
+CONFIG_HWSPINLOCK=y
+CONFIG_HWSPINLOCK_OMAP=y
+# CONFIG_ARM_ARCH_TIMER_EVTSTREAM is not set
+# CONFIG_ARM_PMU is not set
+CONFIG_EXT2_FS=y
+CONFIG_EXT3_FS=y
+CONFIG_MSDOS_FS=y
+CONFIG_VFAT_FS=y
+CONFIG_EXFAT_FS=y
+CONFIG_TMPFS=y
+CONFIG_JFFS2_FS=y
+# CONFIG_JFFS2_FS_WRITEBUFFER is not set
+CONFIG_JFFS2_COMPRESSION_OPTIONS=y
+CONFIG_JFFS2_LZO=y
+CONFIG_JFFS2_RUBIN=y
+CONFIG_JFFS2_CMODE_NONE=y
+CONFIG_UBIFS_FS=y
+CONFIG_UBIFS_FS_ADVANCED_COMPR=y
+# CONFIG_UBIFS_FS_ZLIB is not set
+# CONFIG_UBIFS_FS_ZSTD is not set
+# CONFIG_UBIFS_FS_XATTR is not set
+CONFIG_NFS_FS=y
+CONFIG_ROOT_NFS=y
+CONFIG_NLS_CODEPAGE_437=y
+CONFIG_NLS_ISO8859_1=y
+CONFIG_KEYS=y
+CONFIG_SECURITY=y
+# CONFIG_INTEGRITY is not set
+CONFIG_LSM="yama,loadpin,safesetid,integrity"
+# CONFIG_CRYPTO_MANAGER_DISABLE_TESTS is not set
+CONFIG_CRYPTO_DEV_OMAP=y
+CONFIG_CRYPTO_DEV_OMAP_SHAM=y
+CONFIG_CRYPTO_DEV_OMAP_AES=y
+CONFIG_CRYPTO_DEV_OMAP_DES=y
+CONFIG_CRC_CCITT=y
+CONFIG_CRC_T10DIF=y
+CONFIG_CRC_ITU_T=y
+CONFIG_CRC7=y
+CONFIG_LIBCRC32C=y
+CONFIG_PRINTK_TIME=y
+# CONFIG_SYMBOLIC_ERRNAME is not set
+CONFIG_DEBUG_FS=y
+CONFIG_STACKTRACE=y
+# CONFIG_FTRACE is not set
+# CONFIG_RUNTIME_TESTING_MENU is not set
-- 
2.34.1

Re: [PATCH] Update Nanobone

[Mark Jackson]

Any update on this patch ?
Did it ever get through ?
Do I need to re-submit for some reason ?

Regards
Mark J.

Re: [PATCH] Update Nanobone

[Andreas Kemnade]

Hi,

On Tue, 8 Nov 2022 17:18:54 +0000
Mark Jackson <mpfj@newflow.co.uk> wrote:

> Any update on this patch ?
> Did it ever get through ?

it got probably caught in peoples "internal spam filter"
reasons: 
 - bad subject line 
     look at  git log arch/arm/boot/dts/am335x-nano.dts for sane values
 - bad recipient list
     get_maintainer.pl is your friend

Hmm, you already have contributed long time ago, it looks better:
Author: Mark Jackson <mpfj-list@newflow.co.uk>
Date:   Thu Dec 15 10:52:13 2016 +0000

    ARM: dts: Update Nanobone dts file to add external FRAM chip

That looks ok. But maybe reread the documentation/SubmittingPatches again


Regards,
Andreas

Re: [PATCH] Update Nanobone

[Tony Lindgren]

Hi,

* Andreas Kemnade <andreas@kemnade.info> [221108 18:38]:
> Hi,
> 
> On Tue, 8 Nov 2022 17:18:54 +0000
> Mark Jackson <mpfj@newflow.co.uk> wrote:
> 
> > Any update on this patch ?
> > Did it ever get through ?
> 
> it got probably caught in peoples "internal spam filter"
> reasons: 
>  - bad subject line 
>      look at  git log arch/arm/boot/dts/am335x-nano.dts for sane values
>  - bad recipient list
>      get_maintainer.pl is your friend
> 
> Hmm, you already have contributed long time ago, it looks better:
> Author: Mark Jackson <mpfj-list@newflow.co.uk>
> Date:   Thu Dec 15 10:52:13 2016 +0000
> 
>     ARM: dts: Update Nanobone dts file to add external FRAM chip
> 
> That looks ok. But maybe reread the documentation/SubmittingPatches again

Hmm yeah please use similar subject line with the prefix for the dts
changes.

Looking at the dts changes only, the changes for status = "okay" changes
should not be needed for devices enabled by default. Seems like the other
changes are for rs485, please describe why the changes are made in the
patch description.

The separate defconfig should not be needed. Please send any defconfig
changes to multi_v7_defconfig or omap2plu_defconfig as separate patches.

Note that you can run make savedefconfig first to produce a minimal diff.
Then if adding device drivers, please add them as loadable modules where
possible.

Regards,

Tony

Re: [PATCH] Update Nanobone

[Mark Jackson]

On Wed, 9 Nov 2022 at 07:37, Tony Lindgren <tony@atomide.com> wrote:
>
> The separate defconfig should not be needed. Please send any defconfig
> changes to multi_v7_defconfig or omap2plu_defconfig as separate patches.
>
> Note that you can run make savedefconfig first to produce a minimal diff.
> Then if adding device drivers, please add them as loadable modules where
> possible.

But using the omap2plus_defconfig increases my kernel to 4.7MB

My "custom" one has been specifically designed for the NANO platform
and currently sits at about 3.7MB (which nicely fits into the ~4MB memory
bank allocated to the kernel)

Hence the use of my custom defconfig.

I don't have modules enabled as the platform functionality is pretty fixed.

The defconfig I posted was created using savedefconfig.
Is it still wrong ?

Cheers
Mark J.

Re: [PATCH] Update Nanobone

[Tony Lindgren]

Hi,

* Mark Jackson <mpfj@newflow.co.uk> [221109 14:35]:
> On Wed, 9 Nov 2022 at 07:37, Tony Lindgren <tony@atomide.com> wrote:
> >
> > The separate defconfig should not be needed. Please send any defconfig
> > changes to multi_v7_defconfig or omap2plu_defconfig as separate patches.
> >
> > Note that you can run make savedefconfig first to produce a minimal diff.
> > Then if adding device drivers, please add them as loadable modules where
> > possible.
> 
> But using the omap2plus_defconfig increases my kernel to 4.7MB
>
> My "custom" one has been specifically designed for the NANO platform
> and currently sits at about 3.7MB (which nicely fits into the ~4MB memory
> bank allocated to the kernel)
> 
> Hence the use of my custom defconfig.

Maybe host your defconfig somewhere on a device related wiki page?

We got rid of the board specific config files in the kernel years ago in
favor of just a few generic ones.

> I don't have modules enabled as the platform functionality is pretty fixed.

OK nothing wrong with that, multi_v7_defconfig and omap2plus_defconfig are
trying to be more generic and distro friendly.

> The defconfig I posted was created using savedefconfig.
> Is it still wrong ?

Nothing wrong with that, except it should be hosted with the device
related documentation and not in the kernel :)

Regards,

Tony