annotate gsm-fw/L1/stand/README @ 1017:759b3cbf46aa

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author Mychaela Falconia <falcon@ivan.Harhan.ORG>
date Mon, 21 Mar 2016 06:05:57 +0000
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9e605ec89ed0 gsm-fw/L1/stand: starting work on our version of standalone L1
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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1 In their internal development environment, TI had a way to build L1 standalone,
9e605ec89ed0 gsm-fw/L1/stand: starting work on our version of standalone L1
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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2 i.e., omitting the G23 protocol stack and other large and complex pieces of the
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3 full firmware. Such an ability is essential for sane development, and the
9e605ec89ed0 gsm-fw/L1/stand: starting work on our version of standalone L1
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4 abundant references to OP_L1_STANDALONE throughout the codebase confirm that TI
9e605ec89ed0 gsm-fw/L1/stand: starting work on our version of standalone L1
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5 had it indeed.
9e605ec89ed0 gsm-fw/L1/stand: starting work on our version of standalone L1
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6
9e605ec89ed0 gsm-fw/L1/stand: starting work on our version of standalone L1
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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7 However, we (FreeCalypso) don't have a way to build an OP_L1_STANDALONE image
9e605ec89ed0 gsm-fw/L1/stand: starting work on our version of standalone L1
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8 exactly the way TI did it - we don't have all of the necessary source - the
9e605ec89ed0 gsm-fw/L1/stand: starting work on our version of standalone L1
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9 glue pieces specific to this configuration are missing. Nor do we necessarily
9e605ec89ed0 gsm-fw/L1/stand: starting work on our version of standalone L1
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10 need to imitate what TI did in this department: it appears that TI's standalone
9e605ec89ed0 gsm-fw/L1/stand: starting work on our version of standalone L1
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11 L1 build omitted GPF (with the exception of OS and OSX) and everything that
9e605ec89ed0 gsm-fw/L1/stand: starting work on our version of standalone L1
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12 lives in Riviera land, but for us the situation is different: we already have
9e605ec89ed0 gsm-fw/L1/stand: starting work on our version of standalone L1
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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13 a successful build with Riviera and GPF, but no L1, thus we simply need to add
9e605ec89ed0 gsm-fw/L1/stand: starting work on our version of standalone L1
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14 L1 to what we have. Our idea of standalone L1 simply means building without
9e605ec89ed0 gsm-fw/L1/stand: starting work on our version of standalone L1
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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15 the G23 stack, which we have yet to begin integrating.
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16
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17 In the standard firmware build, there is a component called L1 PEI. It is part
9e605ec89ed0 gsm-fw/L1/stand: starting work on our version of standalone L1
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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18 of the G23 stack, and has header and library dependencies of the latter - thus
9e605ec89ed0 gsm-fw/L1/stand: starting work on our version of standalone L1
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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19 it is *not* part of the L1 code proper. However, it performs some essential
9e605ec89ed0 gsm-fw/L1/stand: starting work on our version of standalone L1
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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20 initialization steps, and runs the L1A task. We don't know how TI handled
9e605ec89ed0 gsm-fw/L1/stand: starting work on our version of standalone L1
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21 these functions in their standalone L1 build - we don't have that part of their
9e605ec89ed0 gsm-fw/L1/stand: starting work on our version of standalone L1
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22 source, not even in the otherwise complete LoCosto version, not even if we were
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23 targeting LoCosto hardware.
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24
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25 Our solution: we are going to lift l1_pei out of LoCosto's g23m-gsm, and hack
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Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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26 up a special version of it that won't have the standard complement of G23
9e605ec89ed0 gsm-fw/L1/stand: starting work on our version of standalone L1
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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27 header and library dependencies. It is virtually certain that TI did something
9e605ec89ed0 gsm-fw/L1/stand: starting work on our version of standalone L1
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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28 different, but our hack-solution should work for our needs.
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29
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30 Because our standalone L1 build is a specially stripped-down version of the
9e605ec89ed0 gsm-fw/L1/stand: starting work on our version of standalone L1
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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31 regular fw build, and not at all like TI's standalone L1, we do NOT define
9e605ec89ed0 gsm-fw/L1/stand: starting work on our version of standalone L1
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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32 OP_L1_STANDALONE. Instead we have a different preprocessor symbol:
9e605ec89ed0 gsm-fw/L1/stand: starting work on our version of standalone L1
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
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33 CONFIG_L1_STANDALONE.
616
4d40f9a99445 gsm-fw/L1/stand: plan to use L1IF forwarder entity
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents: 613
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34
4d40f9a99445 gsm-fw/L1/stand: plan to use L1IF forwarder entity
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents: 613
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35 The standard version of l1_pei calls vsi_c_open() to get queue handles of
4d40f9a99445 gsm-fw/L1/stand: plan to use L1IF forwarder entity
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents: 613
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36 several G23 stack entities; it connects by name to "PL", "MMI", and if GPRS is
4d40f9a99445 gsm-fw/L1/stand: plan to use L1IF forwarder entity
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents: 613
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37 enabled, also to "GRR", "LLC" and "SND". If we leave these connect-by-name
4d40f9a99445 gsm-fw/L1/stand: plan to use L1IF forwarder entity
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents: 613
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38 calls unchanged in our L1 standalone version, our pei_init() will always return
4d40f9a99445 gsm-fw/L1/stand: plan to use L1IF forwarder entity
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents: 613
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39 PEI_ERROR and never successfully initialize, which would not be very useful.
4d40f9a99445 gsm-fw/L1/stand: plan to use L1IF forwarder entity
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents: 613
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40 If we removed these vsi_c_open() calls and the associated OSX queue setup, the
4d40f9a99445 gsm-fw/L1/stand: plan to use L1IF forwarder entity
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents: 613
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41 first osx_send_prim() addressed to the queue in question will crash, so that
4d40f9a99445 gsm-fw/L1/stand: plan to use L1IF forwarder entity
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents: 613
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42 approach wouldn't be useful either.
4d40f9a99445 gsm-fw/L1/stand: plan to use L1IF forwarder entity
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents: 613
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43
4d40f9a99445 gsm-fw/L1/stand: plan to use L1IF forwarder entity
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents: 613
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44 What we would like to do is redirect all outbound messages emitted by our
4d40f9a99445 gsm-fw/L1/stand: plan to use L1IF forwarder entity
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents: 613
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45 standalone L1 to the debug serial interface, using GPF's TST entity, just as if
4d40f9a99445 gsm-fw/L1/stand: plan to use L1IF forwarder entity
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents: 613
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46 an L1 REDIRECT or DUPLICATE command was given to a complete GSM fw image.
4d40f9a99445 gsm-fw/L1/stand: plan to use L1IF forwarder entity
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents: 613
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47 However, simply connecting our queues to TST won't work, as TST is not designed
4d40f9a99445 gsm-fw/L1/stand: plan to use L1IF forwarder entity
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents: 613
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48 to receive "internal" protocol stack primitives directly. When the routing
4d40f9a99445 gsm-fw/L1/stand: plan to use L1IF forwarder entity
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents: 613
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49 facility is used to DUPLICATE or REDIRECT a prim to an external entity, the
4d40f9a99445 gsm-fw/L1/stand: plan to use L1IF forwarder entity
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents: 613
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50 code in gpf/frame/route.c sends a special "wrapper" prim to TST, and we need to
4d40f9a99445 gsm-fw/L1/stand: plan to use L1IF forwarder entity
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents: 613
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51 replicate this wrapping in order to achieve the same effect.
4d40f9a99445 gsm-fw/L1/stand: plan to use L1IF forwarder entity
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents: 613
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52
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Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents: 613
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53 Our solution: we are going to construct a special forwarder entity called L1IF,
4d40f9a99445 gsm-fw/L1/stand: plan to use L1IF forwarder entity
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents: 613
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54 and the connect-by-name calls in l1_pei which normally point to PL, MMI etc
4d40f9a99445 gsm-fw/L1/stand: plan to use L1IF forwarder entity
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents: 613
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55 will point to L1IF instead. L1IF will run in the passive body variant, and its
4d40f9a99445 gsm-fw/L1/stand: plan to use L1IF forwarder entity
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents: 613
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56 pei_primitive() function will replicate the routing facility's logic for
4d40f9a99445 gsm-fw/L1/stand: plan to use L1IF forwarder entity
Michael Spacefalcon <msokolov@ivan.Harhan.ORG>
parents: 613
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57 forwarding PS primitives to TST. Whew!