GXReadMemMetric

Syntax

#include <revolution/gx.h>

void GXReadMemMetric( u32*           cp_req,
                      u32*           tc_req,
                      u32*           cpu_rd_req,
                      u32*           cpu_wr_req,
                      u32*           dsp_req,
                      u32*           io_req,
                      u32*           vi_req,
                      u32*           pe_req,
                      u32*           rf_req,
                      u32*           fi_req  );

Arguments

cp_req	Returns a CP request counter value as a 32-bit unsigned integer.
tc_req	Returns a TC request counter value as a 32-bit unsigned integer.
cpu_rd_req	Returns a CPU read request counter value as a 32-bit unsigned integer.
cpu_wr_req	Returns a CPU write request counter value as a 32-bit unsigned integer.
dsp_req	Returns a DPS request counter value as a 32-bit unsigned integer.
io_req	Returns an IO request counter value as a 32-bit unsigned integer.
vi_req	Returns a VI request counter value as a 32-bit unsigned integer.
pe_req	Returns a PE request counter value as a 32-bit unsigned integer.
rf_req	Returns an RF request counter value as a 32-bit unsigned integer.
fi_req	Returns an FI request counter value as a 32-bit unsigned integer.

Return Values

None.

Description

The graphics processor (GP) can count many internal events that give detailed information on performance. This function returns the number of memory requests made by each memory master. The counters can be cleared by calling the GXClearMemMetric function.

Note: This function can measure only access to internal memory (MEM1 region) of the system. It cannot measure access to external memory (MEM2 region).

u32 cp_req, tc_req, cpu_rd_req, cpu_wr_req, dsp_req, io_req, vi_req, pe_req;
 u32 rf_req, fi_req;
 
 GXClearMemMetric();
 
 // Draw Object(s)

// wait until object drawn
 GXSetDrawSync(0xbeef);
 while (0xbeef != GXReadDrawSync())
     ;
 
 metric = GXReadMemMetric(&cp_req,
                          &tc_req,
                          &cpu_rd_req,
                          &cpu_wr_req,
                          &dsp_req,
                          &io_req,
                          &vi_req,
                          &pe_req,
                          &rf_req,
                          &fi_req );
 
 OSReport("Number command processor requests:  %d\n", cp_req);

Each request results in a 32-byte transaction on the main memory bus.

Memory Counter Details

cp_req

The command processor (CP) is responsible for reading the graphics FIFO, reading display lists (in the GXCallDisplayList function), and servicing vertex cache misses. This metric returns the number of memory read requests issued by the command processor.

tc_req

Returns the number of memory read requests issued by the texture cache (TC).

cpu_rd_req

Returns the number of memory read requests made by the CPU.

cp_wr_req

Returns the number of memory write requests made by the CPU.

dsp_req

Returns the number of memory requests made by the audio DSP.

io_req

Returns the number of memory requests made by IO devices.

vi_req

Returns the number of memory read requests made by the video interface (VI).

pe_req

Returns the number of memory write requests made by the pixel engine (PE). These include texture copies (GXCopyTex) and display copies (GXCopyDisp).

rf_req

Returns the number of memory refresh requests.

fi_req

Returns the number of forced idle (FI) requests, which are dummy requests required to switch the bus direction (read to write, or write to read).

Revision History

2006/03/01 Initial version.

CONFIDENTIAL