MX25R64 cannot enter DPD.

RE: MX25R64 cannot enter DPD.

helsing — Fri, 12 Aug 2022 13:13:52 GMT

Hi Bon, great to hear that it works. Thank you for updating us on the result.

Best regards,

Håkon

RE: MX25R64 cannot enter DPD.

bon.chen — Fri, 12 Aug 2022 03:09:00 GMT

Hello Nordic team,

Thank you for the great support! This issue has been solved.

Best Regards

Bon

RE: MX25R64 cannot enter DPD.

helsing — Wed, 10 Aug 2022 20:09:31 GMT

Hi Bon, here is the pull request with a fix for the missing pull-up on the CSN line: https://github.com/zephyrproject-rtos/zephyr/pull/48645

"When there is no external pull-up on the CSN line and the line
is put into the low-power mode (input direction and disconnected
buffer), after some time its level falls to low and some flash
chips, like for example MX25R64, exit the Deep Power-down mode
when that happens. To prevent this, activate the GPIO internal
pull-up for this line in boards that do not have the external
pull-up on it."

RE: MX25R64 cannot enter DPD.

helsing — Fri, 29 Jul 2022 21:48:02 GMT

Hi Bon,

The root cause of this issue with DPD could be the lack of pull up for the CSN pin.

For nRF52840 DK you may add a pull up for the QSPI CSN signal in such way:

        qspi_sleep: qspi_sleep {
                group1 {
                        psels = <NRF_PSEL(QSPI_SCK, 0, 19)>,
                                <NRF_PSEL(QSPI_IO0, 0, 20)>,
                                <NRF_PSEL(QSPI_IO1, 0, 21)>,
                                <NRF_PSEL(QSPI_IO2, 0, 22)>,
                                <NRF_PSEL(QSPI_IO3, 0, 23)>;
                        low-power-enable;
                };
                group2 {
                        psels = <NRF_PSEL(QSPI_CSN, 0, 17)>;
                        low-power-enable;
                        bias-pull-up;
                };
        };

You could do this directly in the board files: zephyr/boards/arm/nrf52840dk_nrf52840/nrf52840dk_nrf52840-pinctrl.dtsi

In other words, add a special group2 for CSN with the added parameter

bias-pull-up

It is probably tidier/more conventional to add this as an overlay in your project folder.

RE: MX25R64 cannot enter DPD.

bon.chen — Wed, 27 Jul 2022 15:19:26 GMT

Hello Helsing,

Great. Looking forward to the fix and update.

Regards

Bon

RE: MX25R64 cannot enter DPD.

helsing — Wed, 27 Jul 2022 14:20:51 GMT

Hi Bon,

Sorry for the delay, I have been out of office.

I am working on this and will keep you updated.

RE: MX25R64 cannot enter DPD.

bon.chen — Fri, 08 Jul 2022 08:53:27 GMT

Perhaps the next SDK will fix this issue.

This case will be closed.

RE: MX25R64 cannot enter DPD.

bon.chen — Thu, 07 Jul 2022 15:12:58 GMT

Hi Anthony,

I don't have an answer. Perhaps we should wait for the reply from Nordic team.

Regards

Bon

RE: MX25R64 cannot enter DPD.

Anthony Yuan — Thu, 07 Jul 2022 11:43:20 GMT

Hi Bon,

I met the same issue and do you have any tips/solutions?

After called pm_device_action_run(qspi_nor_dev, PM_DEVICE_ACTION_SUSPEND) in my application code,

From RTT log, I can see enter_dpd() and nrfx_qspi_uninit() entered

00> [00:00:02.043,701] <dbg> qspi_nor.enter_dpd: enter_dpd enter
00> [00:00:02.044,128] <dbg> qspi_nor.qspi_nor_pm_action: nrfx_qspi_uninit

And I collected wave form, it is properly set the dpd command to external flash (0xB9), and then CS is set to high after that

But after around 13 ms, CS and SI were set to low

I have no idea how the CS has been set to low and I am looking into the nrf qspi driver.

IMO, the sample code running on 52840DK will have the same result.

Regards,

Anthony Yuan

RE: MX25R64 cannot enter DPD.

helsing — Wed, 29 Jun 2022 13:34:16 GMT

Hi,

Please try to renaming the overlay file so that it is named the same as your board(unless you have a custom board which is named 'app'). Assuming your board is nRF52840 DK, then your overlay file should be named 'nrf52840dk_nrf52840.overlay'.

To verify that the overlay us used, please check your build folder: build/zephyr/zephyr.dts, and verify that the code from the overlay file is there:

    chosen {
        nordic,pm-ext-flash = &mx25r64;
    };

Best regards,

Håkon

RE: MX25R64 cannot enter DPD.

bon.chen — Mon, 27 Jun 2022 08:10:42 GMT

Hi,

I tried your suggested solution but CS is still low. Below is my .overlay and your prj.conf. I renamed prj.conf to prj.conf.txt because devzone doesn't allow me to upload files in .conf format.

devzone.nordicsemi.com/.../app.overlay

devzone.nordicsemi.com/.../prj.conf.txt

Thanks.

RE: MX25R64 cannot enter DPD.

helsing — Fri, 24 Jun 2022 11:51:30 GMT

Hello Bon,

Are you seeing any activity on the other pins connected to MX25R64?

I found another case, nRF52840 Zephyr dual QSPI MX25R64 flash example, that looks somewhat similar to yours. Try copying from the suggested solution into your .overlay:

&qspi {
	status = "okay";
	sck-pin = <19>;
	io-pins = <20>, <21>;
	csn-pins = <17>;
	mx25r64: mx25r6435f@0 {
		compatible = "nordic,qspi-nor";
		reg = <0>;
		quad-enable-requirements = "NONE";
		/* MX24R64 supports only pp and pp4io */
		writeoc = "pp";
		/* MX24R64 supports all readoc options */
		readoc = "fastread";
		sck-frequency = <8000000>;
		label = "MX25R64";
		jedec-id = [c2 28 17];
		sfdp-bfp = [
			e5 20 f1 ff  ff ff ff 03  44 eb 08 6b  08 3b 04 bb
			ee ff ff ff  ff ff 00 ff  ff ff 00 ff  0c 20 0f 52
			10 d8 00 ff  23 72 f5 00  82 ed 04 cc  44 83 68 44
			30 b0 30 b0  f7 c4 d5 5c  00 be 29 ff  f0 d0 ff ff
		];
		size = <67108864>;
		has-dpd;
		t-enter-dpd = <10000>;
		t-exit-dpd = <35000>;
	};
};

Could you please post your .overlay and your prj.conf file?