BSD style Open Source alternatives to CMSIS?
From the reading the current CMSIS 2.0 license, it seems the intention is not to prevent you from developing your software as open-source or otherwise, but more about covering ARM's ass. I.e. they want to make sure that you don't claim ownership of the code itself or any IP that might be in it, and also that it's used to develop code complying to CMSIS and not for some other purpose.


  
  Subject to the provisions of Clauses 2, 3, 4 and 5, ARM hereby
  grants to you under any intellectual
  property that is (a) owned or freely
  licensable by ARM without payment to
  unaffiliated third parties and (b)
  either embodied in either or both the
  Source Code and Specification, as
  applicable, or Necessary (defined in
  Clause 4 below) to copy or implement
  an applications binary interface
  compliant with the Specification, a
  perpetual, non-exclusive,
  non-transferable, royalty free,
  worldwide licence to:
  (i)       use and copy
  the Specification for the purpose of
  developing, having developed,
  manufacturing, having manufactured,
  offering to sell, selling, supplying
  or otherwise distributing products
  which comply with the Specification;
  (ii)       use, copy, modify and
  sublicence the Source Code (in source
  or object code form) solely for the
  purpose of developing, having
  developed, manufacturing, having
  manufactured, offering to sell,
  selling, supplying or otherwise
  distributing products which comply
  with the Specification, provided that
  you preserve all copyright notices
  included in the Source Code.
  The Source Code and Specification are owned by ARM or its licensors and
  are protected by copyright laws and
  international copyright treaties as
  well as other intellectual property
  laws and treaties. The Source Code and
  Specification are licensed not sold.
  Except as specifically licensed in
  accordance with Clause 1, you acquire
  no right, title or interest in the
  Source Code and Specification or any
  intellectual property embodied
  therein. In no event shall the
  licences granted in accordance with
  Clause 1 be construed as granting you,
  expressly or by implication, estoppel
  or otherwise, a licence to use any ARM
  technology except the Source Code and
  Specification.  Except as provided in
  Clause 1, no right is granted to you
  to sublicense the rights granted to
  you under this Licence.
  


That said, if you're still uncomfortable with those terms, you can just take the datasheet and make the headers yourself. Guys from microbuilder.eu has done just that, and released their LPC1114 and LPC1343 codebase under BSD.