Re: [PATCH RFC net-next 4/9] net: pcs: xpcs: add Qualcomm Nord platform support

On Wed, Sep 23, 2026 at 02:07:07PM +0200, Andrew Lunn wrote:

On Wed, Sep 23, 2026 at 06:37:30AM +0530, Mohd Ayaan Anwar wrote:

quoted

Qualcomm Nord exposes the DesignWare XPCS register blocks through
separate direct-MMIO windows instead of the standard contiguous
MMD/register layout. Add accessors that translate MMD accesses to the
Nord windows:

  MMD 3 (PCS), standard registers: SR_XS at 0x0000

What does standard mean? 802.3 C45.2.3 defines registers 3.0 -
3.32767 as standardised. 

quoted

  MMD 3 (PCS), vendor registers:   VR_XS at 0x2000

and 3.32768 - 3.65535 as vendor.

However, with a length of 0x2000, there is only space for 8192 of the
standardised registers, and 0x1000 gives 4096 vendor registers.

quoted

  MMD 1 (PMA/PMD):                  SR_PMA at 0x3000
  MMD 31 (VEND2), standard regs:    SR_MII at 0x4000

What do you mean by standard registers when talking about VEND2?

This is incorrect, these are non-standard VEND2 registers.

quoted

  MMD 31 (VEND2), vendor registers: VR_MII at 0x5000

Overall, it's a mess, with some registers marked as reserved, and some
not defined. I will go through the list once again and document them
properly. Thank you for the pointers, this is the first time I am
working with this IP and I have found the specific version of the
databook to be confusing.

	Ayaan