+/**
+ * \b mips32_pracc_sync_cache
+ *
+ * Synchronize Caches to Make Instruction Writes Effective
+ * (ref. doc. MIPS32 Architecture For Programmers Volume II: The MIPS32 Instruction Set,
+ * Document Number: MD00086, Revision 2.00, June 9, 2003)
+ *
+ * When the instruction stream is written, the SYNCI instruction should be used
+ * in conjunction with other instructions to make the newly-written instructions effective.
+ *
+ * Explanation :
+ * A program that loads another program into memory is actually writing the D- side cache.
+ * The instructions it has loaded can't be executed until they reach the I-cache.
+ *
+ * After the instructions have been written, the loader should arrange
+ * to write back any containing D-cache line and invalidate any locations
+ * already in the I-cache.
+ *
+ * You can do that with cache instructions, but those instructions are only available in kernel mode,
+ * and a loader writing instructions for the use of its own process need not be privileged software.
+ *
+ * In the latest MIPS32/64 CPUs, MIPS provides the synci instruction,
+ * which does the whole job for a cache-line-sized chunk of the memory you just loaded:
+ * That is, it arranges a D-cache write-back and an I-cache invalidate.
+ *
+ * To employ synci at user level, you need to know the size of a cache line,
+ * and that can be obtained with a rdhwr SYNCI_Step
+ * from one of the standard “hardware registers”.
+ */
+static int mips32_pracc_sync_cache(struct mips_ejtag *ejtag_info,
+ uint32_t start_addr, uint32_t end_addr)
+{
+ static const uint32_t code[] = {
+ /* start: */
+ MIPS32_MTC0(15,31,0), /* move $15 to COP0 DeSave */
+ MIPS32_LUI(15,UPPER16(MIPS32_PRACC_STACK)), /* $15 = MIPS32_PRACC_STACK */
+ MIPS32_ORI(15,15,LOWER16(MIPS32_PRACC_STACK)),
+ MIPS32_SW(8,0,15), /* sw $8,($15) */
+ MIPS32_SW(9,0,15), /* sw $9,($15) */
+ MIPS32_SW(10,0,15), /* sw $10,($15) */
+ MIPS32_SW(11,0,15), /* sw $11,($15) */
+
+ MIPS32_LUI(8,UPPER16(MIPS32_PRACC_PARAM_IN)), /* $8 = MIPS32_PRACC_PARAM_IN */
+ MIPS32_ORI(8,8,LOWER16(MIPS32_PRACC_PARAM_IN)),
+ MIPS32_LW(9,0,8), /* Load write start_addr to $9 */
+ MIPS32_LW(10,4,8), /* Load write end_addr to $10 */
+
+ MIPS32_RDHWR(11, MIPS32_SYNCI_STEP), /* $11 = MIPS32_SYNCI_STEP */
+ MIPS32_BEQ(11,0,6), /* beq $11, $0, end */
+ MIPS32_NOP,
+ /* synci_loop : */
+ MIPS32_SYNCI(0,9), /* synci 0($9) */
+ MIPS32_SLTU(8,10,9), /* sltu $8, $10, $9 # $8 = $10 < $9 ? 1 : 0 */
+ MIPS32_BNE(8,0,NEG16(3)), /* bne $8, $0, synci_loop */
+ MIPS32_ADDU(9, 9, 11), /* $9 += MIPS32_SYNCI_STEP */
+ MIPS32_SYNC,
+ /* end: */
+ MIPS32_LW(11,0,15), /* lw $11,($15) */
+ MIPS32_LW(10,0,15), /* lw $10,($15) */
+ MIPS32_LW(9,0,15), /* lw $9,($15) */
+ MIPS32_LW(8,0,15), /* lw $8,($15) */
+ MIPS32_B(NEG16(24)), /* b start */
+ MIPS32_MFC0(15,31,0), /* move COP0 DeSave to $15 */
+ };
+
+ /* TODO remove array */
+ uint32_t *param_in = malloc(2 * sizeof(uint32_t));
+ int retval;
+ param_in[0] = start_addr;
+ param_in[1] = end_addr;
+
+ retval = mips32_pracc_exec(ejtag_info, ARRAY_SIZE(code), code, 2, param_in, 0, NULL, 1);
+
+ free(param_in);
+
+ return retval;
+}
+
+/**
+ * \b mips32_pracc_clean_invalidate_cache
+ *
+ * Writeback D$ and Invalidate I$
+ * so that the instructions written can be visible to CPU
+ */
+static int mips32_pracc_clean_invalidate_cache(struct mips_ejtag *ejtag_info,
+ uint32_t start_addr, uint32_t end_addr)
+{
+ static const uint32_t code[] = {
+ /* start: */
+ MIPS32_MTC0(15,31,0), /* move $15 to COP0 DeSave */
+ MIPS32_LUI(15,UPPER16(MIPS32_PRACC_STACK)), /* $15 = MIPS32_PRACC_STACK */
+ MIPS32_ORI(15,15,LOWER16(MIPS32_PRACC_STACK)),
+ MIPS32_SW(8,0,15), /* sw $8,($15) */
+ MIPS32_SW(9,0,15), /* sw $9,($15) */
+ MIPS32_SW(10,0,15), /* sw $10,($15) */
+ MIPS32_SW(11,0,15), /* sw $11,($15) */
+
+ MIPS32_LUI(8,UPPER16(MIPS32_PRACC_PARAM_IN)), /* $8 = MIPS32_PRACC_PARAM_IN */
+ MIPS32_ORI(8,8,LOWER16(MIPS32_PRACC_PARAM_IN)),
+ MIPS32_LW(9,0,8), /* Load write start_addr to $9 */
+ MIPS32_LW(10,4,8), /* Load write end_addr to $10 */
+ MIPS32_LW(11,8,8), /* Load write clsiz to $11 */
+
+ /* cache_loop: */
+ MIPS32_SLTU(8,10,9), /* sltu $8, $10, $9 : $8 <- $10 < $9 ? */
+ MIPS32_BGTZ(8,6), /* bgtz $8, end */
+ MIPS32_NOP,
+
+ MIPS32_CACHE(MIPS32_CACHE_D_HIT_WRITEBACK,0,9), /* cache Hit_Writeback_D, 0($9) */
+ MIPS32_CACHE(MIPS32_CACHE_I_HIT_INVALIDATE,0,9), /* cache Hit_Invalidate_I, 0($9) */
+
+ MIPS32_ADDU(9,9,11), /* $9 += $11 */
+
+ MIPS32_B(NEG16(7)), /* b cache_loop */
+ MIPS32_NOP,
+ /* end: */
+ MIPS32_LW(11,0,15), /* lw $11,($15) */
+ MIPS32_LW(10,0,15), /* lw $10,($15) */
+ MIPS32_LW(9,0,15), /* lw $9,($15) */
+ MIPS32_LW(8,0,15), /* lw $8,($15) */
+ MIPS32_B(NEG16(25)), /* b start */
+ MIPS32_MFC0(15,31,0), /* move COP0 DeSave to $15 */
+ };
+
+ /**
+ * Find cache line size in bytes
+ */
+ uint32_t conf;
+ uint32_t dl, clsiz;
+
+ mips32_cp0_read(ejtag_info, &conf, 16, 1);
+ dl = (conf & MIPS32_CONFIG1_DL_MASK) >> MIPS32_CONFIG1_DL_SHIFT;
+
+ /* dl encoding : dl=1 => 4 bytes, dl=2 => 8 bytes, etc... */
+ clsiz = 0x2 << dl;
+
+ /* TODO remove array */
+ uint32_t *param_in = malloc(3 * sizeof(uint32_t));
+ int retval;
+ param_in[0] = start_addr;
+ param_in[1] = end_addr;
+ param_in[2] = clsiz;
+
+ retval = mips32_pracc_exec(ejtag_info, ARRAY_SIZE(code), code, 3, param_in, 0, NULL, 1);
+
+ free(param_in);
+
+ return retval;
+}
+
+