[coreboot-gerrit] Change in em100[master]: Incorporate protocol-notes.txt into specification

[Stefan Reinauer (Code Review)]

Stefan Reinauer has uploaded this change for review. ( https://review.coreboot.org/c/em100/+/36807 )

Change subject: Incorporate protocol-notes.txt into specification
......................................................................

Incorporate protocol-notes.txt into specification

We now know that these values from the config files are FPGA
register writes. Hence let's include them in the spec and drop
the additional file. Unfortunately these are not very well
documented at this time.

Change-Id: I4eefdde358299428b751baee15e57b4ee7b2d16c
Signed-off-by: Stefan Reinauer 
---
D protocol-notes.txt
M usb-protocol.md
2 files changed, 97 insertions(+), 21 deletions(-)

git pull ssh://review.coreboot.org:29418/em100 refs/changes/07/36807/1

diff --git a/protocol-notes.txt b/protocol-notes.txt
deleted file mode 100644
index 15da29f..0000000
--- a/protocol-notes.txt
+++ /dev/null
@@ -1,16 +0,0 @@
-= Some protocol notes =
-
- out 16 bytes: 0x23 x a0 a1: write chip reg x with a0.a1 (x is always even)
-     x = 0x32: always 0xff 0xff (?)
-     x = 0x3a: set chip size to (a1+1) * 0x10000
-     x = 0x38: various values (?)
-     x = 0x40: sometimes: a0 = lowbyte of device id (for 16bit did?), a1 = device id (for 8bit did) ?
-     x = 0x42: a0 = vendor id, a1 = highbyte of device id for 16bit did or device id for 8bit did (?)
-     x = 0x44: always 0x03 0x18 (?)
-     x = 0x46: a0 = various, a1 = always 0x30? (?)
-     x = 0x48: a0 = various, a1 = always 0xc0? (?)
-
- out 16 bytes: 0x11 x a0 a1: write reg x with a0.a1 -> Set Voltage
-     x = 2: REF+ voltage
-     x = 3: REF- voltage
-     x = 4: Buffer VCC
diff --git a/usb-protocol.md b/usb-protocol.md
index cfdf61d..f27dba2 100644
--- a/usb-protocol.md
+++ b/usb-protocol.md
@@ -187,7 +187,7 @@
 Value: Register Value
 ```

-See chapter 7 for more information on FPGA commands.
+See chapter 2.6 for more information on FPGA commands.

### 2.5. Switch FPGA configuration image

@@ -227,11 +227,103 @@
 EM100Pro-G2 | 3.3         | 2.014        |

-### 2.6. FPGA Reconfiguration
+### 2.6. FPGA Registers

-Description of some FPGA command registers (incomplete).
+Description of some FPGA command registers (incomplete). Each register
+has a 1 byte address and is 2 bytes wide (referred to as a0, a1). This includes
+some information of the former file protocol-notes.txt. Please help complete this
+information.

-#### 2.6.1. Default Address Length Setting
+#### 2.6.1. ????
+
+FPGA command:
+
+| Address | R/W | Description               |
+|---------|-----|---------------------------|
+| 0x32    | ?/W | ??                        |
+
+Written through the config files for each emulated chip.
+Data written is always observed as 0xff 0xff (?)
+
+#### 2.6.2. ????
+
+FPGA command:
+
+| Address | R/W | Description               |
+|---------|-----|---------------------------|
+| 0x38    | ?/W | ??                        |
+
+Written through the config files for each emulated chip.
+Data written is various values (?)
+
+#### 2.6.3. Set Chip Size
+
+FPGA command:
+
+| Address | R/W | Description               |
+|---------|-----|---------------------------|
+| 0x3a    | ?/W | Set Chip Size             |
+
+Written through the config files for each emulated chip.
+Sets chip size to (a1+1) * 0x10000 (?)
+
+#### 2.6.4. ????
+
+FPGA command:
+
+| Address | R/W | Description               |
+|---------|-----|---------------------------|
+| 0x40    | ?/W | ??                        |
+
+Written through the config files for each emulated chip.
+sometimes: a0 = lowbyte of device id (for 16bit did?), a1 = device id (for 8bit
+did)
+
+#### 2.6.5. ????
+
+FPGA command:
+
+| Address | R/W | Description               |
+|---------|-----|---------------------------|
+| 0x42    | ?/W | ??                        |
+
+Written through the config files for each emulated chip.
+a0 = vendor id, a1 = highbyte of device id for 16bit did or device id for 8bit did (?)
+
+#### 2.6.6. ????
+
+FPGA command:
+
+| Address | R/W | Description               |
+|---------|-----|---------------------------|
+| 0x44    | ?/W | ??                        |
+
+Written through the config files for each emulated chip.
+Always 0x03 0x18 (?)
+
+#### 2.6.7. ????
+
+FPGA command:
+
+| Address | R/W | Description               |
+|---------|-----|---------------------------|
+| 0x46    | ?/W | ??                        |
+
+Written through the config files for each emulated chip.
+a0 = various, a1 = always 0x30? (?)
+
+#### 2.6.8. ????
+
+FPGA command:
+
+| Address | R/W | Description               |
+|---------|-----|---------------------------|
+| 0x48    | ?/W | ??                        |
+
+Written through the config files for each emulated chip.
+a0 = various, a1 = always 0xc0? (?)
+
+#### 2.6.9. Default Address Length Setting

FPGA command:

@@ -250,7 +342,7 @@
 EM100Pro    | 2.27        | 0.091        |
 EM100Pro-G2 | 3.3         | 2.014        |

-#### 2.6.2. CS Pin Selection
+#### 2.6.10. CS Pin Selection

FPGA command: