SK-AM62B-P1: AM62 GPMC driver / config

Hi Bin:

Q1. There are 2 files: ti,gpmc.yaml + ti,gpmc-child.yaml in this folder, which one should I study?

Q2. What's the ti,gpmc-child.yaml used for? if the AM62 is the host to control the Dual Port Ram?

Q3. In the ti,gpmc.yaml , there is no enum for AM62, it only shows this, can you confirm if this is okay to use on AM62?

- enum
- ti,am3352-gpmc
- ti,am64-gpmc
- ti,omap2420-gpmc
- ti,omap2430-gpmc
- ti,omap3430-gpmc
- ti,omap4430-gpmc

Q4. What are the kernel configs I need to turn on this feature? plz address.

       Or it default is activated.?

BR Rio

Should I study those for the Dual Port Ram when it is used by customer?

please see below. 

And the red words should be fixed for AM62?

./vendor-prefixes.yaml: "^(at25|bm|devbus|dmacap|dsa|exynos|fsi[ab]|gpio-fan|gpio-key|gpio|gpmc|hdmi|i2c-gpio),.*": true
./mtd/ti,gpmc-nand.yaml:$id: devicetree.org/.../ti,gpmc-nand.yaml
./mtd/ti,gpmc-nand.yaml: - $ref: "/schemas/memory-controllers/ti,gpmc-child.yaml"
./mtd/ti,gpmc-nand.yaml: gpmc: memory-controller@50000000 {
./mtd/ti,gpmc-nand.yaml: compatible = "ti,am3352-gpmc";
./mtd/ti,gpmc-nand.yaml: gpmc,num-cs = <7>;
./mtd/ti,gpmc-nand.yaml: gpmc,num-waitpins = <2>;
./mtd/ti,gpmc-nand.yaml: interrupt-parent = <&gpmc>;
./mtd/ti,gpmc-nand.yaml: rb-gpios = <&gpmc 0 GPIO_ACTIVE_HIGH>; /* gpmc_wait0 */
./mtd/ti,gpmc-nand.yaml: gpmc,device-width = <1>;
./mtd/ti,gpmc-onenand.yaml:$id: devicetree.org/.../ti,gpmc-onenand.yaml
./mtd/ti,gpmc-onenand.yaml: - $ref: "/schemas/memory-controllers/ti,gpmc-child.yaml"
./mtd/ti,gpmc-onenand.yaml: gpmc: memory-controller@6e000000 {
./mtd/ti,gpmc-onenand.yaml: compatible = "ti,omap3430-gpmc";
./mtd/ti,gpmc-onenand.yaml: gpmc,num-cs = <8>;
./mtd/ti,gpmc-onenand.yaml: gpmc,num-waitpins = <4>;
./net/smsc,lan9115.yaml:# "gpmc,*", ...) to be found, that actually depend on the compatible value of

Hi Rio,

I am out of office today. I will review your questions next week and get back to you.

Hi Rio,

Rio Chan said:

Q1. There are 2 files: ti,gpmc.yaml + ti,gpmc-child.yaml in this folder, which one should I study?

The ti,gpmc.taml describes the GPMC controller, while ti,gpmc-child.yaml describes the devices connected to GPMC, for example, NAND, NOR, or FPGA...

Rio Chan said:

Q3. In the ti,gpmc.yaml , there is no enum for AM62, it only shows this, can you confirm if this is okay to use on AM62?

Please see the gpmc0 node in kernel device tree k3-am62-main.dtsi, it uses "ti,am64-gpmc".

Rio Chan said:

Q4. What are the kernel configs I need to turn on this feature? plz address.

CONFIG_OMAP_GPMC

Rio Chan said:

       Or it default is activated.?

It is already enabled in the kernel defconfig.