view rvinterf/include/limits.h @ 958:ca6e969be6ee

rvinterf suite: raise MAX_PKT_FROM_TARGET to 1600
author Mychaela Falconia <falcon@freecalypso.org>
date Thu, 08 Jun 2023 02:47:48 +0000
parents e7502631a0f9
children
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/*
 * For sizing our buffers etc in the rvinterf suite, including the local
 * UNIX domain socket protocol between rvinterf and fc-tmsh etc, we need
 * to have some limits on the message sizes in both host->target and
 * target->host directions.
 *
 * For the host->target direction, the choice of message size limit is
 * easy: the packet Rx code in RVT on the target side also has a limit
 * (quite naturally, as it needs to use a static buffer to reassemble
 * incoming packets as they arrive at the UART in unpredictable interrupt-
 * sized chunks), so we set our limit to match that in RVT.
 */

#define	MAX_PKT_TO_TARGET	255

/*
 * In the other direction (target->host), there is no fixed limit
 * definition easily visible in the target fw code: any fw component
 * can call rvt_send_trace_cpy() or rvt_mem_alloc() followed by
 * rvt_send_trace_no_cpy(), or some higher-level API that reduces to
 * these functions, with a message of any size, subject only to memory
 * limits, which obviously aren't as strict as a #define'd maximum
 * message size.
 *
 * With current FreeCalypso fw, unchanged from classic TCS211 in this
 * aspect, the largest RVTMUX packets emitted by the fw are G23M PS
 * primitives forwarded externally via GPF routing mechanism, and some
 * of them exceed our previous arbitrary limit of 512 bytes.  However,
 * the largest output packet size that can be generated via this
 * mechanism equals the largest partition size in GPF partition pool
 * configuration, and that largest size is 1600 bytes.  Hence we have
 * our answer as to what maximum packet size we need to support.
 */

#define	MAX_PKT_FROM_TARGET	1600

/*
 * Both limit definitions above counts all bytes between the opening and
 * closing STX flags, but not DLEs inserted for binary transparency.
 */