source: rtems/c/src/lib/libbsp/m68k/uC5282/startup/bspstart.c @ 1eb65053

4.104.114.84.95
Last change on this file since 1eb65053 was ac9bbe7, checked in by Eric Norum <WENorum@…>, on 04/21/05 at 00:25:53

Try insructioin-only cache.

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[572484f]1/*
2 *  BSP startup
3 *
4 *  This routine starts the application.  It includes application,
5 *  board, and monitor specific initialization and configuration.
6 *  The generic CPU dependent initialization has been performed
7 *  before this routine is invoked.
8 *
9 *  Author:
10 *    David Fiddes, D.J@fiddes.surfaid.org
11 *    http://www.calm.hw.ac.uk/davidf/coldfire/
12 *
13 *  COPYRIGHT (c) 1989-1998.
14 *  On-Line Applications Research Corporation (OAR).
15 *  Copyright assigned to U.S. Government, 1994.
16 *
17 *  The license and distribution terms for this file may be
18 *  found in the file LICENSE in this distribution or at
19 *
20 *  http://www.OARcorp.com/rtems/license.html.
21 *
22 *  $Id$
23 */
24
25#include <bsp.h>
26#include <rtems/libio.h>
27#include <rtems/libcsupport.h>
28#include <string.h>
[7eab0f78]29#include <errno.h>
[572484f]30 
31/*
32 *  The original table from the application and our copy of it with
33 *  some changes.
34 */
35extern rtems_configuration_table Configuration;
36rtems_configuration_table  BSP_Configuration;
37rtems_cpu_table Cpu_table;
38char *rtems_progname;
39
40/*
41 * Location of 'VME' access
42 */
43#define VME_ONE_BASE    0x30000000
44#define VME_TWO_BASE    0x31000000
45
46/*
47 * CPU-space access
[cbb615b]48 * The NOP after writing the CACR is there to address the following issue as
49 * described in "Device Errata MCF5282DE", Rev. 1.7, 09/2004:
50 *
51 * 6 Possible Cache Corruption after Setting  CACR[CINV]
52 * 6.1 Description
53 * The cache on the MCF5282 was enhanced to function as a unified data and
54 * instruction cache, an instruction cache, or an operand cache.  The cache
55 * function and organization is controlled by the cache control register (CACR).
56 * The CINV (Bit 24 = cache invalidate) bit in the CACR causes a cache clear.
57 * If the cache is configured as a unified cache and the CINV bit is set, the
58 * scope of the cache clear is controlled by two other bits in the CACR,
59 * INVI (BIT 21 = CINV instruction cache only) and INVD (BIT 20 = CINV data
60 * cache only).  These bits allow the entire cache, just the instruction
61 * portion of the cache, or just the data portion of the cache to be cleared.
62 * If a write to the CACR is performed to clear the cache (CINV = BIT 24 set)
63 * and only a partial clear will be done (INVI = BIT 21 or INVD = BIT 20 set),
64 * then cache corruption may  occur.
65 *
66 * 6.2 Workaround
67 * All loads of the CACR that perform a cache clear operation (CINV = BIT 24)
68 * should be followed immediately by a NOP instruction.  This avoids the cache
69 * corruption problem.
70 * DATECODES AFFECTED: All
[572484f]71 */
[ac9bbe7]72#define m68k_set_cacr_nop(_cacr) asm volatile ("movec %0,%%cacr\n\tnop" : : "d" (_cacr))
73#define m68k_set_cacr(_cacr) asm volatile ("movec %0,%%cacr" : : "d" (_cacr))
[572484f]74#define m68k_set_acr0(_acr0) asm volatile ("movec %0,%%acr0" : : "d" (_acr0))
75#define m68k_set_acr1(_acr1) asm volatile ("movec %0,%%acr1" : : "d" (_acr1))
76
77/*
[d5fe91e]78 * Read/write copy of cache registers
[ac9bbe7]79 *   Split instruction/data or instruction-only
[572484f]80 *   Allow CPUSHL to invalidate a cache line
81 *   Enable buffered writes
82 *   No burst transfers on non-cacheable accesses
83 *   Default cache mode is *disabled* (cache only ACRx areas)
84 */
[d5fe91e]85uint32_t mcf5282_cacr_mode = MCF5XXX_CACR_CENB |
[ac9bbe7]86#ifndef RTEMS_MCF5282_BSP_ENABLE_DATA_CACHE
87                             MCF5XXX_CACR_DISD |
88#endif
[d5fe91e]89                             MCF5XXX_CACR_DBWE |
90                             MCF5XXX_CACR_DCM;
91uint32_t mcf5282_acr0_mode = 0;
92uint32_t mcf5282_acr1_mode = 0;
[572484f]93/*
94 * Cannot be frozen
95 */
96void _CPU_cache_freeze_data(void) {}
97void _CPU_cache_unfreeze_data(void) {}
98void _CPU_cache_freeze_instruction(void) {}
99void _CPU_cache_unfreeze_instruction(void) {}
100
101/*
102 * Write-through data cache -- flushes are unnecessary
103 */
104void _CPU_cache_flush_1_data_line(const void *d_addr) {}
105void _CPU_cache_flush_entire_data(void) {}
106
107void _CPU_cache_enable_instruction(void)
108{
109    rtems_interrupt_level level;
110
111    rtems_interrupt_disable(level);
[d5fe91e]112    mcf5282_cacr_mode &= ~MCF5XXX_CACR_DIDI;
113    m68k_set_cacr(mcf5282_cacr_mode);
[572484f]114    rtems_interrupt_enable(level);
115}
116
117void _CPU_cache_disable_instruction(void)
118{
119    rtems_interrupt_level level;
120
121    rtems_interrupt_disable(level);
[d5fe91e]122    mcf5282_cacr_mode |= MCF5XXX_CACR_DIDI;
123    m68k_set_cacr(mcf5282_cacr_mode);
[572484f]124    rtems_interrupt_enable(level);
125}
126
127void _CPU_cache_invalidate_entire_instruction(void)
128{
[ac9bbe7]129    m68k_set_cacr_nop(mcf5282_cacr_mode | MCF5XXX_CACR_CINV | MCF5XXX_CACR_INVI);
[572484f]130}
131
132void _CPU_cache_invalidate_1_instruction_line(const void *addr)
133{
[518edef]134    /*
135     * Top half of cache is I-space
136     */
137    addr = (void *)((int)addr | 0x400);
138    asm volatile ("cpushl %%bc,(%0)" :: "a" (addr));
[572484f]139}
140
141void _CPU_cache_enable_data(void)
142{
[ac9bbe7]143#ifdef RTEMS_MCF5282_BSP_ENABLE_DATA_CACHE
[572484f]144    rtems_interrupt_level level;
145
146    rtems_interrupt_disable(level);
[ac9bbe7]147    mcf5282_cacr_mode &= ~MCF5XXX_CACR_CENB;
[d5fe91e]148    m68k_set_cacr(mcf5282_cacr_mode);
[572484f]149    rtems_interrupt_enable(level);
[ac9bbe7]150#endif
[572484f]151}
152
153void _CPU_cache_disable_data(void)
154{
[ac9bbe7]155#ifdef RTEMS_MCF5282_BSP_ENABLE_DATA_CACHE
[572484f]156    rtems_interrupt_level level;
157
[518edef]158    rtems_interrupt_disable(level);
[572484f]159    rtems_interrupt_disable(level);
[ac9bbe7]160    mcf5282_cacr_mode |= MCF5XXX_CACR_CENB;
[d5fe91e]161    m68k_set_cacr(mcf5282_cacr_mode);
[572484f]162    rtems_interrupt_enable(level);
[ac9bbe7]163#endif
[572484f]164}
165
166void _CPU_cache_invalidate_entire_data(void)
167{
[ac9bbe7]168#ifdef RTEMS_MCF5282_BSP_ENABLE_DATA_CACHE
169    m68k_set_cacr_nop(mcf5282_cacr_mode | MCF5XXX_CACR_CINV | MCF5XXX_CACR_INVD);
170#endif
[572484f]171}
172
173void _CPU_cache_invalidate_1_data_line(const void *addr)
174{
[ac9bbe7]175#ifdef RTEMS_MCF5282_BSP_ENABLE_DATA_CACHE
[518edef]176    /*
177     * Bottom half of cache is D-space
178     */
179    addr = (void *)((int)addr & ~0x400);
180    asm volatile ("cpushl %%bc,(%0)" :: "a" (addr));
[ac9bbe7]181#endif
[572484f]182}
183
184/*
185 *  Use the shared implementations of the following routines
186 */
187void bsp_postdriver_hook(void);
[0b2c943]188void bsp_libc_init( void *, uint32_t, int );
[d75023e]189void bsp_pretasking_hook(void);         /* m68k version */
[572484f]190
191/*
192 *  bsp_start
193 *
194 *  This routine does the bulk of the system initialisation.
195 */
196void bsp_start( void )
197{
198  extern char _WorkspaceBase[];
[0eff7b8]199  extern char _RamBase[], _RamSize[];
[572484f]200  extern unsigned long  _M68k_Ramsize;
201
[d75023e]202  _M68k_Ramsize = (unsigned long)_RamSize;      /* RAM size set in linker script */
[572484f]203
204  /*
205   *  Allocate the memory for the RTEMS Work Space.  This can come from
206   *  a variety of places: hard coded address, malloc'ed from outside
207   *  RTEMS world (e.g. simulator or primitive memory manager), or (as
208   *  typically done by stock BSPs) by subtracting the required amount
209   *  of work space from the last physical address on the CPU board.
210   */
211
212  /*
213   *  Need to "allocate" the memory for the RTEMS Workspace and
214   *  tell the RTEMS configuration where it is.  This memory is
215   *  not malloc'ed.  It is just "pulled from the air".
216   */
217
218  BSP_Configuration.work_space_start = (void *)_WorkspaceBase;
219
220  /*
221   *  initialize the CPU table for this BSP
222   */
223  Cpu_table.pretasking_hook = bsp_pretasking_hook;  /* init libc, etc. */
224  Cpu_table.postdriver_hook = bsp_postdriver_hook;
225  Cpu_table.do_zero_of_workspace = TRUE;
226  Cpu_table.interrupt_stack_size = 4096;
227
228  Cpu_table.interrupt_vector_table = (m68k_isr *)0; /* vectors at start of RAM */
229
230    /*
231     * Invalidate the cache and disable it
232     */
[d5fe91e]233    m68k_set_acr0(mcf5282_acr0_mode);
234    m68k_set_acr1(mcf5282_acr1_mode);
[ac9bbe7]235    m68k_set_cacr_nop(MCF5XXX_CACR_CINV);
[572484f]236
237    /*
[059c95e]238     * Cache SDRAM
[572484f]239     */
[d5fe91e]240    mcf5282_acr0_mode = MCF5XXX_ACR_AB((uint32_t)_RamBase)     |
241                        MCF5XXX_ACR_AM((uint32_t)_RamSize-1)   |
242                        MCF5XXX_ACR_EN                         |
243                        MCF5XXX_ACR_BWE                        |
244                        MCF5XXX_ACR_SM_IGNORE;
245    m68k_set_acr0(mcf5282_acr0_mode);
[572484f]246
247    /*
248     * Enable the cache
249     */
[d5fe91e]250    m68k_set_cacr(mcf5282_cacr_mode);
[572484f]251
252    /*
253     * Set up CS* space (fake 'VME')
254     *   Two A24/D16 spaces, supervisor data acces
255     */
256    MCF5282_CS1_CSAR = MCF5282_CS_CSAR_BA(VME_ONE_BASE);
257    MCF5282_CS1_CSMR = MCF5282_CS_CSMR_BAM_16M |
258                       MCF5282_CS_CSMR_CI |
259                       MCF5282_CS_CSMR_SC |
260                       MCF5282_CS_CSMR_UC |
261                       MCF5282_CS_CSMR_UD |
262                       MCF5282_CS_CSMR_V;
263    MCF5282_CS1_CSCR = MCF5282_CS_CSCR_PS_16;
264    MCF5282_CS2_CSAR = MCF5282_CS_CSAR_BA(VME_TWO_BASE);
265    MCF5282_CS2_CSMR = MCF5282_CS_CSMR_BAM_16M |
266                       MCF5282_CS_CSMR_CI |
267                       MCF5282_CS_CSMR_SC |
268                       MCF5282_CS_CSMR_UC |
269                       MCF5282_CS_CSMR_UD |
270                       MCF5282_CS_CSMR_V;
271    MCF5282_CS2_CSCR = MCF5282_CS_CSCR_PS_16;
272}
273
[0b2c943]274uint32_t bsp_get_CPU_clock_speed(void)
[572484f]275{
276    extern char _CPUClockSpeed[];
[0b2c943]277    return( (uint32_t)_CPUClockSpeed);
[572484f]278}
[7eab0f78]279
[5b6111b]280/*
281 * Interrupt controller allocation
282 */
[d75023e]283rtems_status_code
284bsp_allocate_interrupt(int level, int priority)
[5b6111b]285{
286    static char used[7];
287    rtems_interrupt_level l;
[d75023e]288    rtems_status_code ret = RTEMS_RESOURCE_IN_USE;
[5b6111b]289
290    if ((level < 1) || (level > 7) || (priority < 0) || (priority > 7))
[d75023e]291        return RTEMS_INVALID_NUMBER;
[5b6111b]292    rtems_interrupt_disable(l);
293    if ((used[level-1] & (1 << priority)) == 0) {
294        used[level-1] |= (1 << priority);
[d75023e]295        ret = RTEMS_SUCCESSFUL;
[5b6111b]296    }
297    rtems_interrupt_enable(l);
298    return ret;
299}
300
[7eab0f78]301/*
[12993b3]302 * Arcturus bootloader system calls
[7eab0f78]303 */
[12993b3]304#define syscall_return(type, ret)                      \
305do {                                                   \
306   if ((unsigned long)(ret) >= (unsigned long)(-64)) { \
307      errno = -(ret);                                  \
308      ret = -1;                                        \
309   }                                                   \
310   return (type)(ret);                                 \
[7eab0f78]311} while (0)
[12993b3]312#define syscall_1(type,name,d1type,d1)                      \
[8af3643]313type bsp_##name(d1type d1)                                  \
[12993b3]314{                                                           \
315   long ret;                                                \
316   register long __d1 __asm__ ("%d1") = (long)d1;           \
[16ae480]317   __asm__ __volatile__ ("move.l %1,%%d0\n\t"               \
[12993b3]318                         "trap #2\n\t"                      \
319                         "move.l %%d0,%0"                   \
320                         : "=g" (ret)                       \
[8af3643]321                         : "i" (SysCode_##name), "d" (__d1) \
[12993b3]322                         : "d0" );                          \
323   syscall_return(type,ret);                                \
[7eab0f78]324}
[16ae480]325#define syscall_2(type,name,d1type,d1,d2type,d2)            \
[8af3643]326type bsp_##name(d1type d1, d2type d2)                       \
[16ae480]327{                                                           \
328   long ret;                                                \
329   register long __d1 __asm__ ("%d1") = (long)d1;           \
330   register long __d2 __asm__ ("%d2") = (long)d2;           \
331   __asm__ __volatile__ ("move.l %1,%%d0\n\t"               \
332                         "trap #2\n\t"                      \
333                         "move.l %%d0,%0"                   \
334                         : "=g" (ret)                       \
[8af3643]335                         : "i" (SysCode_##name), "d" (__d1),\
[16ae480]336                                                 "d" (__d2) \
337                         : "d0" );                          \
338   syscall_return(type,ret);                                \
339}
[8af3643]340#define syscall_3(type,name,d1type,d1,d2type,d2,d3type,d3)  \
341type bsp_##name(d1type d1, d2type d2, d3type d3)            \
342{                                                           \
343   long ret;                                                \
344   register long __d1 __asm__ ("%d1") = (long)d1;           \
345   register long __d2 __asm__ ("%d2") = (long)d2;           \
346   register long __d3 __asm__ ("%d3") = (long)d3;           \
347   __asm__ __volatile__ ("move.l %1,%%d0\n\t"               \
348                         "trap #2\n\t"                      \
349                         "move.l %%d0,%0"                   \
350                         : "=g" (ret)                       \
351                         : "i" (SysCode_##name), "d" (__d1),\
352                                                 "d" (__d2),\
353                                                 "d" (__d3) \
354                         : "d0" );                          \
355   syscall_return(type,ret);                                \
356}
357#define SysCode_reset              0 /* reset */
358#define SysCode_program            5 /* program flash memory */
359#define SysCode_gethwaddr         12 /* get hardware address */
360#define SysCode_getbenv           14 /* get bootloader environment variable */
361#define SysCode_setbenv           15 /* get bootloader environment variable */
362#define SysCode_flash_erase_range 19 /* erase a section of flash */
363#define SysCode_flash_write_range 20 /* write a section of flash */
[12993b3]364syscall_1(unsigned const char *, gethwaddr, int, a)
365syscall_1(const char *, getbenv, const char *, a)
[16ae480]366syscall_2(int, program, bsp_mnode_t *, chain, int, flags)
[8af3643]367syscall_3(int, flash_erase_range, volatile unsigned short *, flashptr, int, start, int, end);
368syscall_3(int, flash_write_range, volatile unsigned short *, flashptr, bsp_mnode_t *, chain, int, offset);
[d75023e]369
370/*
371 * 'Extended BSP' routines
372 * Should move to cpukit/score/cpu/m68k/cpu.c someday.
373 */
374
375rtems_status_code bspExtInit(void) { return RTEMS_SUCCESSFUL; }
376int BSP_enableVME_int_lvl(unsigned int level) { return 0; }
377int BSP_disableVME_int_lvl(unsigned int level) { return 0; }
378
379/*
[a81e4f1]380 * 'VME' interrupt support
[402f4df]381 * Interrupt vectors 192-255 are set aside for use by external logic which
382 * drives IRQ1*.  The actual interrupt source is read from the external
383 * logic at FPGA_IRQ_INFO.  The most-significant bit of the least-significant
384 * byte read from this location is set as long as the external logic has
385 * interrupts to be serviced.  The least-significant six bits indicate the
386 * interrupt source within the external logic and are used to select the
387 * specified interupt handler.
[d75023e]388 */
[a7e6bc96]389#define NVECTOR 256
[a81e4f1]390#define FPGA_VECTOR (64+1)  /* IRQ1* pin connected to external FPGA */
[402f4df]391#define FPGA_EPPAR  MCF5282_EPORT_EPPAR_EPPA1_LEVEL
[a81e4f1]392#define FPGA_EPDDR  MCF5282_EPORT_EPDDR_EPDD1
393#define FPGA_EPIER  MCF5282_EPORT_EPIER_EPIE1
394#define FPGA_EPPDR  MCF5282_EPORT_EPPDR_EPPD1
395#define FPGA_IRQ_INFO    *((vuint16 *)(0x31000000 + 0xfffffe))
[a7e6bc96]396
[d75023e]397static struct handlerTab {
398    BSP_VME_ISR_t func;
399    void         *arg;
[a7e6bc96]400} handlerTab[NVECTOR];
[d75023e]401
402BSP_VME_ISR_t
403BSP_getVME_isr(unsigned long vector, void **pusrArg)
404{
[a7e6bc96]405    if (vector >= NVECTOR)
[d75023e]406        return (BSP_VME_ISR_t)NULL;
407    if (pusrArg)
408        *pusrArg = handlerTab[vector].arg;
409    return handlerTab[vector].func;
410}
411
412static rtems_isr
[a7e6bc96]413trampoline (rtems_vector_number v)
[d75023e]414{
[a81e4f1]415    /*
416     * Handle FPGA interrupts until all have been consumed
417     */
418    if (v == FPGA_VECTOR) {
[402f4df]419        while (((v = FPGA_IRQ_INFO) & 0x80) != 0) {
[a81e4f1]420            v = 192 + (v & 0x3f);
421            if (handlerTab[v].func)
422                (*handlerTab[v].func)(handlerTab[v].arg, (unsigned long)v);
423            else
424                rtems_fatal_error_occurred(v);
425        }
426    }
427    else if (handlerTab[v].func)
[d75023e]428        (*handlerTab[v].func)(handlerTab[v].arg, (unsigned long)v);
429}
430
431int
432BSP_installVME_isr(unsigned long vector, BSP_VME_ISR_t handler, void *usrArg)
433{
434    rtems_isr_entry old_handler;
[a81e4f1]435    rtems_interrupt_level level;
[d75023e]436
[a81e4f1]437    /*
438     * Register the handler information
439     */
[a7e6bc96]440    if (vector >= NVECTOR)
[d75023e]441        return -1;
442    handlerTab[vector].func = handler;
443    handlerTab[vector].arg = usrArg;
[a81e4f1]444
445    /*
446     * If this is an external FPGA ('VME') vector set up the real IRQ.
447     */
448    if ((vector >= 192) && (vector <= 255)) {
449        int i;
450        static volatile int setupDone;
451        rtems_interrupt_disable(level);
452        if (setupDone) {
453            rtems_interrupt_enable(level);
454            return 0;
455        }
456        MCF5282_EPORT_EPPAR &= ~FPGA_EPPAR;
457        MCF5282_EPORT_EPDDR &= ~FPGA_EPDDR;
458        MCF5282_EPORT_EPIER |=  FPGA_EPIER;
[402f4df]459        MCF5282_INTC0_IMRL &= ~(MCF5282_INTC_IMRL_INT1 |
460                                MCF5282_INTC_IMRL_MASKALL);
[a81e4f1]461        setupDone = 1;
462        i = BSP_installVME_isr(FPGA_VECTOR, NULL, NULL);
463        rtems_interrupt_enable(level);
464        return i;
465    }
466
467    /*
468     * Make the connection between the interrupt and the local handler
469     */
[be129f69]470    rtems_interrupt_catch(trampoline, vector, &old_handler);
[d75023e]471
472    /*
[a7e6bc96]473     * Find an unused level/priority if this is an on-chip (INTC0)
474     * source and this is the first time the source is being used.
475     * Interrupt sources 1 through 7 are fixed level/priority
[d75023e]476     */
477    if ((vector >= 65) && (vector <= 127)) {
478        int l, p;
[a7e6bc96]479        int source = vector - 64;
480        static unsigned char installed[8];
[d75023e]481
[f3f4be7]482        rtems_interrupt_disable(level);
483        if (installed[source/8] & (1 << (source % 8))) {
484            rtems_interrupt_enable(level);
[a7e6bc96]485            return 0;
[f3f4be7]486        }
[a7e6bc96]487        installed[source/8] |= (1 << (source % 8));
[f3f4be7]488        rtems_interrupt_enable(level);
[d75023e]489        for (l = 1 ; l < 7 ; l++) {
[c2ab8b0]490            for (p = 0 ; p < 8 ; p++) {
[a7e6bc96]491                if ((source < 8)
492                 || (bsp_allocate_interrupt(l,p) == RTEMS_SUCCESSFUL)) {
[8e712757]493                    if (source >= 8)
[a7e6bc96]494                        *(&MCF5282_INTC0_ICR1 + (source - 1)) =
[d75023e]495                                                       MCF5282_INTC_ICR_IL(l) |
496                                                       MCF5282_INTC_ICR_IP(p);
497                    rtems_interrupt_disable(level);
[a7e6bc96]498                    if (source >= 32)
499                        MCF5282_INTC0_IMRH &= ~(1 << (source - 32));
[d75023e]500                    else
[a7e6bc96]501                        MCF5282_INTC0_IMRL &= ~((1 << source) |
[d75023e]502                                                MCF5282_INTC_IMRL_MASKALL);
503                    rtems_interrupt_enable(level);
504                    return 0;
505                }
506            }
507        }
[a7e6bc96]508        return -1;
[d75023e]509    }
[a7e6bc96]510    return 0;
[d75023e]511}
512
513int
514BSP_removeVME_isr(unsigned long vector, BSP_VME_ISR_t handler, void *usrArg)
515{
[a7e6bc96]516    if (vector >= NVECTOR)
[d75023e]517        return -1;
518    if ((handlerTab[vector].func != handler)
519     || (handlerTab[vector].arg != usrArg))
520        return -1;
521    handlerTab[vector].func = (BSP_VME_ISR_t)NULL;
522    return 0;
523}
524
525int
526BSP_vme2local_adrs(unsigned am, unsigned long vmeaddr, unsigned long *plocaladdr)
527{
528    unsigned long offset;
529
530    switch (am) {
531    default:    return -1;
[008c4b5]532    case VME_AM_SUP_SHORT_IO: offset = 0x31FF0000; break; /* A16/D16 */
[d75023e]533    case VME_AM_STD_SUP_DATA: offset = 0x30000000; break; /* A24/D16 */
[008c4b5]534    case VME_AM_EXT_SUP_DATA: offset = 0x31000000; break; /* A32/D32 */
[d75023e]535    }
536    *plocaladdr = vmeaddr + offset;
537    return 0;
538}
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