Add a subcommand to display a hexdump of transceiver EEPROM page (#2379)

* Add a subcommand to display a hexdump of transceiver EEPROM page

What I did
Added a subcommand to display the hexdump of transceiver EEPROM page specified by the user.
"sfputil show eeprom-hexdump -p <port_name> -r <page_number>" has been added for this purpose and it requires both port name and page number as mandatory inputs.
Lower page 0h is always displayed and the upper page is displayed based on the page number specified by the user

How to verify it
Verified the utility with 400G DD, 100G QSFP28 and 40G DAC

Signed-off-by: Mihir Patel <patelmi@microsoft.com>

* Added support for SFF-8472 EEPROM dump and addressed PR comments

* Added more test cases

Signed-off-by: Mihir Patel <patelmi@microsoft.com>

* Changed -r option to -n and changed lower string for displaying A2h contents

Signed-off-by: Mihir Patel <patelmi@microsoft.com>

Signed-off-by: Mihir Patel <patelmi@microsoft.com>

sfputil/main.py

@@ -44,6 +44,11 @@
 
 MAX_LPL_FIRMWARE_BLOCK_SIZE = 116 #Bytes
 
+PAGE_SIZE = 128
+PAGE_OFFSET = 128
+
+SFF8472_A0_SIZE = 256
+
 # TODO: We should share these maps and the formatting functions between sfputil and sfpshow
 QSFP_DATA_MAP = {
     'model': 'Vendor PN',
@@ -688,6 +693,148 @@ def eeprom(port, dump_dom, namespace):
 
     click.echo(output)
 
+# 'eeprom-hexdump' subcommand
+@show.command()
+@click.option('-p', '--port', metavar='<port_name>', required=True, help="Display SFP EEPROM hexdump for port <port_name>")
+@click.option('-n', '--page', metavar='<page_number>', help="Display SFP EEEPROM hexdump for <page_number_in_hex>")
+def eeprom_hexdump(port, page):
+    """Display EEPROM hexdump of SFP transceiver(s) for a given port name and page number"""
+    output = ""
+
+    if platform_sfputil.is_logical_port(port) == 0:
+        click.echo("Error: invalid port {}".format(port))
+        print_all_valid_port_values()
+        sys.exit(ERROR_INVALID_PORT)
+
+    if page is None:
+        page = '0'
+
+    logical_port_name = port
+    physical_port = logical_port_to_physical_port_index(logical_port_name)
+
+    if is_port_type_rj45(logical_port_name):
+        click.echo("{}: SFP EEPROM Hexdump is not applicable for RJ45 port".format(port))
+        sys.exit(ERROR_INVALID_PORT)
+
+    try:
+        presence = platform_chassis.get_sfp(physical_port).get_presence()
+    except NotImplementedError:
+        click.echo("Sfp.get_presence() is currently not implemented for this platform")
+        sys.exit(ERROR_NOT_IMPLEMENTED)
+
+    if not presence:
+        click.echo("SFP EEPROM not detected")
+        sys.exit(ERROR_NOT_IMPLEMENTED)
+    else:
+        try:
+            id = platform_chassis.get_sfp(physical_port).read_eeprom(0, 1)
+            if id is None:
+                click.echo("Error: Failed to read EEPROM for offset 0!")
+                sys.exit(ERROR_NOT_IMPLEMENTED)
+        except NotImplementedError:
+            click.echo("Sfp.read_eeprom() is currently not implemented for this platform")
+            sys.exit(ERROR_NOT_IMPLEMENTED)
+
+        if id[0] == 0x3:
+            output = eeprom_hexdump_sff8472(port, physical_port, page)
+        else:
+            output = eeprom_hexdump_sff8636(port, physical_port, page)
+
+    output += '\n'
+
+    click.echo(output)
+
+def eeprom_hexdump_sff8472(port, physical_port, page):
+    try:
+        output = ""
+        indent = ' ' * 8
+        output += 'EEPROM hexdump for port {} page {}h'.format(port, page)
+        output += '\n{}A0h dump'.format(indent)
+        page_dump = platform_chassis.get_sfp(physical_port).read_eeprom(0, SFF8472_A0_SIZE)
+        if page_dump is None:
+            click.echo("Error: Failed to read EEPROM for A0h!")
+            sys.exit(ERROR_NOT_IMPLEMENTED)
+
+        output += hexdump(indent, page_dump, 0)
+        page_dump = platform_chassis.get_sfp(physical_port).read_eeprom(SFF8472_A0_SIZE, PAGE_SIZE)
+        if page_dump is None:
+            click.echo("Error: Failed to read EEPROM for A2h!")
+            sys.exit(ERROR_NOT_IMPLEMENTED)
+        else:
+            output += '\n\n{}A2h dump (lower 128 bytes)'.format(indent)
+            output += hexdump(indent, page_dump, 0)
+
+        page_dump = platform_chassis.get_sfp(physical_port).read_eeprom(SFF8472_A0_SIZE + PAGE_OFFSET + (int(page, base=16) * PAGE_SIZE), PAGE_SIZE)
+        if page_dump is None:
+            click.echo("Error: Failed to read EEPROM for A2h upper page!")
+            sys.exit(ERROR_NOT_IMPLEMENTED)
+        else:
+            output += '\n\n{}A2h dump (upper 128 bytes) page {}h'.format(indent, page)
+            output += hexdump(indent, page_dump, PAGE_OFFSET)
+    except NotImplementedError:
+        click.echo("Sfp.read_eeprom() is currently not implemented for this platform")
+        sys.exit(ERROR_NOT_IMPLEMENTED)
+    except ValueError:
+        click.echo("Please enter a numeric page number")
+        sys.exit(ERROR_NOT_IMPLEMENTED)
+
+    return output
+
+def eeprom_hexdump_sff8636(port, physical_port, page):
+    try:
+        output = ""
+        indent = ' ' * 8
+        output += 'EEPROM hexdump for port {} page {}h'.format(port, page)
+        output += '\n{}Lower page 0h'.format(indent)
+        page_dump = platform_chassis.get_sfp(physical_port).read_eeprom(0, PAGE_SIZE)
+        if page_dump is None:
+            click.echo("Error: Failed to read EEPROM for page 0!")
+            sys.exit(ERROR_NOT_IMPLEMENTED)
+
+        output += hexdump(indent, page_dump, 0)
+        page_dump = platform_chassis.get_sfp(physical_port).read_eeprom(int(page, base=16) * PAGE_SIZE + PAGE_OFFSET, PAGE_SIZE)
+        if page_dump is None:
+            click.echo("Error: Failed to read EEPROM!")
+            sys.exit(ERROR_NOT_IMPLEMENTED)
+        else:
+            output += '\n\n{}Upper page {}h'.format(indent, page)
+            output += hexdump(indent, page_dump, PAGE_OFFSET)
+    except NotImplementedError:
+        click.echo("Sfp.read_eeprom() is currently not implemented for this platform")
+        sys.exit(ERROR_NOT_IMPLEMENTED)
+    except ValueError:
+        click.echo("Please enter a numeric page number")
+        sys.exit(ERROR_NOT_IMPLEMENTED)
+
+    return output
+
+def convert_byte_to_valid_ascii_char(byte):
+    if byte < 32 or 126 < byte:
+        return '.'
+    else:
+        return chr(byte)
+
+def hexdump(indent, data, mem_address):
+    ascii_string = ''
+    result = ''
+    for byte in data:
+        ascii_string = ascii_string + convert_byte_to_valid_ascii_char(byte)
+        byte_string = "{:02x}".format(byte)
+        if mem_address % 16 == 0:
+            mem_address_string = "{:08x}".format(mem_address)
+            result += '\n{}{} '.format(indent, mem_address_string)
+            result += '{} '.format(byte_string)
+        elif mem_address % 16 == 15:
+            result += '{} '.format(byte_string)
+            result += '|{}|'.format(ascii_string)
+            ascii_string = ""
+        elif mem_address % 16 == 7:
+            result += ' {} '.format(byte_string)
+        else:
+            result += '{} '.format(byte_string)
+        mem_address += 1
+
+    return result
 
 # 'presence' subcommand
 @show.command()