From: lkcl Date: Fri, 22 Dec 2023 14:21:13 +0000 (+0000) Subject: (no commit message) X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=0b934a4d48d;p=libreriscv.git --- diff --git a/openpower/sv/remap.mdwn b/openpower/sv/remap.mdwn index 46a614af6..82192a22b 100644 --- a/openpower/sv/remap.mdwn +++ b/openpower/sv/remap.mdwn @@ -259,22 +259,24 @@ disabled: the register's elements are a linear (1D) vector. |0:5 |6:11 | 12:17 | 18:20 | 21:23 |24:27 |28:29 |30:31| Mode | |----- |----- | ------- | ------- | ------ |------|------ |---- | ----- | -|xdimsz|ydimsz| zdimsz | permute | invxyz |offset|skip |mode |Matrix | +|xdimsz|ydimsz| zdimsz | permute | invxyz |offset|skip |0b00 |Matrix | |xdimsz|ydimsz|SVGPR | 11/ |sk1/invxy|offset|elwidth|0b00 |Indexed| |xdimsz|mode | zdimsz | submode2| invxyz |offset|submode|0b01 |DCT/FFT| | rsvd |rsvd |xdimsz | rsvd | invxyz |offset|submode|0b10 |Red/Sum| | | | | | | | |0b11 |rsvd | -`mode` sets different behaviours (straight matrix multiply, FFT, DCT). +`mode` (combined with `permute` when `mode=0b00`) sets different +general behaviours: straight matrix multiply, FFT, DCT, Reduction or Prefix-Sum. -* **mode=0b00** sets straight Matrix Mode -* **mode=0b00** with permute=0b110 or 0b111 sets Indexed Mode +* **mode=0b00** with `permute != 0b110/0b111` sets straight Matrix Mode +* **mode=0b00** with `permute = 0b110/0b111` sets Indexed Mode * **mode=0b01** sets "FFT/DCT" mode and activates submodes * **mode=0b10** sets "Parallel Reduction or Prefix-Sum" Schedules. *Architectural Resource Allocation note: the four SVSHAPE SPRs are best allocated sequentially and contiguously in order that `sv.mtspr` may -be used. This is safe to do as long as `SVSTATE.SVme=0`* +be used to manipulate (save/restore) them. +This is safe to do directly as long as `SVSTATE.SVme=0`* ## Parallel Reduction / Prefix-Sum Mode