Downgrading with linux

You should have grafchokolos modules, and patches installed

This works on 3.55 without a fisical dongle

Use this method to install lower firmware! You can install a newer firmware ex 3.60 with this method but you will be loosing your hombrew

Downgrade Method - Emulating JIG with Linux

1st step – Generating a challenge

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1. ps3dm_usb_dongle_auth /dev/ps3dmproxy gen_challenge

2nd step – Generating a valid response for a challenge

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You need a dongle id. Valid range for dongle IDs is 0×0000 – 0xffff. So choose one, doesn’t matter which one, but some are revoked !!!

1. ps3dm_usb_dongle_auth /dev/ps3dmproxy gen_resp 0xBABE “here is a challenge like this 0xXX 0xXX … of size 20 bytes”

3rd step – Verifying response (Enabling “Product Mode”)

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1. ps3dm_usb_dongle_auth /dev/ps3dmproxy verify_resp 0xBABE

“here is the response from step 2 like this 0xXX 0xXX … of size 20 bytes”

4th step – Checking if “Product Mode” is enabled

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The returned value shouldn’t be 0xff.

1. ps3dm_um /dev/ps3dmproxy read_eprom 0x48C07

5th step - Inspect if CORE_OS_PACKAGE.pkg isn´t damaged

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ps3dm_um /dev/ps3dmproxy inspect_pkg 1 0x9 CORE_OS_PACKAGE.pkg

6th step - Install CORE_OS_PACKAGE.pkg

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ps3dm_um /dev/ps3dmproxy update_pkg 1 0x9 CORE_OS_PACKAGE.pkg

7th step – Disabling “Product Mode”

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1. ps3dm_um /dev/ps3dmproxy write_eprom 0x48C07 0xff

This step is really important, if Produc Mode isn´t disabled you will need a dongle to get out of it

ALTERNATIVE METHOD - not tested

1st step – Enabling product mode

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1. ps3dm_um /dev/ps3dmproxy write_eprom 0x48C07 0xfe

2th step – Checking if “Product Mode” is enabled

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The returned value shouldn’t be 0xff.

1. ps3dm_um /dev/ps3dmproxy read_eprom 0x48C07

3th step - Inspect if CORE_OS_PACKAGE.pkg isn´t damaged

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ps3dm_um /dev/ps3dmproxy inspect_pkg 1 0x9 CORE_OS_PACKAGE.pkg

4th step - Install CORE_OS_PACKAGE.pkg

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ps3dm_um /dev/ps3dmproxy update_pkg 1 0x9 CORE_OS_PACKAGE.pkg

5th step – Disabling “Product Mode”

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1. ps3dm_um /dev/ps3dmproxy write_eprom 0x48C07 0xff

This step is really important, if Produc Mode isn´t disabled you will need a dongle to get out of it

Install debug firmware

High brick risk! Don´t try this if you don´t know what you are doing If you brick with this the only way to recover is with a nor flasher and a proper backup

To install debug firmware, te proper syscon eeprom flags should be set http://www.ps3devwiki.com/index.php?title=Hypervisor_Reverse_Engineering#EEPROM_Offset_Table and EID0 should be resigned and rehashed with the proper target id

or

You could use the data from a debug EID0

Debugging Station Target ID: 0x82

eEID contains

• system model data
• target ID
• PS3 motherboard revision

Other target IDs (might be helpful if someone messes this up)

Targets IDs

• 81 = reference tool
• 82 = debugging station
• 83 = japan
• 84 = USA
• 85 = Europe
• 86 = Korea
• 87 = UK
• 88 = Mexico
• 89 = Australia/New Zealand
• 8A = South Asia (Asia except China, Japan and Taiwan),
• 8B = Taiwan
• 8C = Russia
• 8D = China

"The kernel checks the target id to see if your unit is debug or not and if not it disables all the fancy things such as running unsigned code. So what you want to do is to change 8x into 81 or 82 but this implies resigning the EID section (or at least decrypting the per ps3 encryption from a debug EID target key and reaplying onto a retail)" ;o)