[dv,spi] Set strong drive strength and fast slew rate for SPI pads

[sha-ron]

SPI pads should use strong drive strength and fast slew rate.

[moidx]

CI has the following error:

E00003 power_virus_systemtest.c:1468] DIF-fail: dif_pinmux_pad_write_attrs(&pinmux, kTopEarlgreyDirectPadsSpiHost0Sck, kDifPinmuxPadKindDio, in_attr, &out_attr) returns 13

Code:

opentitan/sw/device/lib/dif/dif_pinmux.c

Lines 307 to 309 in 7e34e67

	if (reg_value != read_value) {
	return kDifError;
	}

This only happens in the sival_rom_ext configuration. Need to check if we are locking pinmux register in that case

[a-will]

CI has the following error:

E00003 power_virus_systemtest.c:1468] DIF-fail: dif_pinmux_pad_write_attrs(&pinmux, kTopEarlgreyDirectPadsSpiHost0Sck, kDifPinmuxPadKindDio, in_attr, &out_attr) returns 13

Code:

opentitan/sw/device/lib/dif/dif_pinmux.c

Lines 307 to 309 in 7e34e67

	if (reg_value != read_value) {
	return kDifError;
	}

This only happens in the sival_rom_ext configuration. Need to check if we are locking pinmux register in that case

It's happening in all FPGA configurations because these pad attributes are not available. Pad attributes should not be written without proper matching against the configuration.

[moidx]

Thanks @a-will for your quick response.

@sha-ron, you will probably want to constraint this configuration to the follow device types:

• kDeviceSilicon
• kDeviceSimDV

[sha-ron]

Thank you @a-will, @moidx for the review and help with the CI failures. I added constrains on the configurations as suggested. Hopefully Ci will pass now.

[a-will]

These should probably be moved to be inside the configure_pinmux_sim() function.

[timothytrippel]

Aren't these attributes already set on the SPI Host 0 data pins? See lines 580 -- 601 in this file. Unless I am missing something here?

[sha-ron]

I think lines 580-601 only set pull up and not drive strength/slew rate.

[timothytrippel]

sure, but can you merge this config with the lines I mentioned above? So we don't set the attributes twice?

[sha-ron]

I tried, but dif_pinmux_pad_attr_flags

opentitan/sw/device/lib/dif/dif_pinmux.h

Line 140 in ae8ac57

typedef enum dif_pinmux_pad_attr_flags {

doesn't have drive_strength and slew_rate fields. Am I missing something here?

[pamaury]

The slew rate is an attribute, not an attribute flag:

opentitan/sw/device/lib/dif/dif_pinmux.h

Line 158 in ae8ac57

dif_pinmux_pad_slew_rate_t slew_rate;

[timothytrippel]

@sha-ron should this change be eventually cherry-picked over to the earlgrey_1.0.0 branch too?

[sha-ron]

@sha-ron should this change be eventually cherry-picked over to the earlgrey_1.0.0 branch too?

Yes, it should be merged also to earlgrey_1.0.0 branch (it is required for GLS simulation).