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hw/ssi/pnv_spi: Use local var seq_index instead of get_seq_index().

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Use a local variable seq_index instead of repeatedly calling
get_seq_index() method and open-code next_sequencer_fsm().

Signed-off-by: Chalapathi V <chalapathi.v@linux.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Message-ID: <20250303141328.23991-3-chalapathi.v@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
This commit is contained in:
Chalapathi V 2025-03-03 08:13:26 -06:00 committed by Nicholas Piggin
parent 17befecda8
commit f1f756f305
1 changed files with 52 additions and 45 deletions
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97
hw/ssi/pnv_spi.c
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@ -227,18 +227,6 @@ static void transfer(PnvSpi *s)
fifo8_reset(&s->rx_fifo);
}
static inline uint8_t get_seq_index(PnvSpi *s)
{
return GETFIELD(SPI_STS_SEQ_INDEX, s->status);
}
static inline void next_sequencer_fsm(PnvSpi *s)
{
uint8_t seq_index = get_seq_index(s);
s->status = SETFIELD(SPI_STS_SEQ_INDEX, s->status, (seq_index + 1));
s->status = SETFIELD(SPI_STS_SEQ_FSM, s->status, SEQ_STATE_INDEX_INCREMENT);
}
/*
* Calculate the N1 counters based on passed in opcode and
* internal register values.
@ -664,6 +652,7 @@ static void operation_sequencer(PnvSpi *s)
bool stop = false; /* Flag to stop the sequencer */
uint8_t opcode = 0;
uint8_t masked_opcode = 0;
uint8_t seq_index;
/*
* Clear the sequencer FSM error bit - general_SPI_status[3]
@ -677,12 +666,17 @@ static void operation_sequencer(PnvSpi *s)
if (GETFIELD(SPI_STS_SEQ_FSM, s->status) == SEQ_STATE_IDLE) {
s->status = SETFIELD(SPI_STS_SEQ_INDEX, s->status, 0);
}
/*
* SPI_STS_SEQ_INDEX of status register is kept in seq_index variable and
* updated back to status register at the end of operation_sequencer().
*/
seq_index = GETFIELD(SPI_STS_SEQ_INDEX, s->status);
/*
* There are only 8 possible operation IDs to iterate through though
* some operations may cause more than one frame to be sequenced.
*/
while (get_seq_index(s) < NUM_SEQ_OPS) {
opcode = s->seq_op[get_seq_index(s)];
while (seq_index < NUM_SEQ_OPS) {
opcode = s->seq_op[seq_index];
/* Set sequencer state to decode */
s->status = SETFIELD(SPI_STS_SEQ_FSM, s->status, SEQ_STATE_DECODE);
/*
@ -699,7 +693,7 @@ static void operation_sequencer(PnvSpi *s)
case SEQ_OP_STOP:
s->status = SETFIELD(SPI_STS_SEQ_FSM, s->status, SEQ_STATE_EXECUTE);
/* A stop operation in any position stops the sequencer */
trace_pnv_spi_sequencer_op("STOP", get_seq_index(s));
trace_pnv_spi_sequencer_op("STOP", seq_index);
stop = true;
s->status = SETFIELD(SPI_STS_SHIFTER_FSM, s->status, FSM_IDLE);
@ -710,7 +704,7 @@ static void operation_sequencer(PnvSpi *s)
case SEQ_OP_SELECT_SLAVE:
s->status = SETFIELD(SPI_STS_SEQ_FSM, s->status, SEQ_STATE_EXECUTE);
trace_pnv_spi_sequencer_op("SELECT_SLAVE", get_seq_index(s));
trace_pnv_spi_sequencer_op("SELECT_SLAVE", seq_index);
/*
* This device currently only supports a single responder
* connection at position 0. De-selecting a responder is fine
@ -721,8 +715,7 @@ static void operation_sequencer(PnvSpi *s)
if (s->responder_select == 0) {
trace_pnv_spi_shifter_done();
qemu_set_irq(s->cs_line[0], 1);
s->status = SETFIELD(SPI_STS_SEQ_INDEX, s->status,
(get_seq_index(s) + 1));
seq_index++;
s->status = SETFIELD(SPI_STS_SHIFTER_FSM, s->status, FSM_DONE);
} else if (s->responder_select != 1) {
qemu_log_mask(LOG_GUEST_ERROR, "Slave selection other than 1 "
@ -747,13 +740,15 @@ static void operation_sequencer(PnvSpi *s)
* applies once a valid responder select has occurred.
*/
s->shift_n1_done = false;
next_sequencer_fsm(s);
seq_index++;
s->status = SETFIELD(SPI_STS_SEQ_FSM, s->status,
SEQ_STATE_INDEX_INCREMENT);
}
break;
case SEQ_OP_SHIFT_N1:
s->status = SETFIELD(SPI_STS_SEQ_FSM, s->status, SEQ_STATE_EXECUTE);
trace_pnv_spi_sequencer_op("SHIFT_N1", get_seq_index(s));
trace_pnv_spi_sequencer_op("SHIFT_N1", seq_index);
/*
* Only allow a shift_n1 when the state is not IDLE or DONE.
* In either of those two cases the sequencer is not in a proper
@ -785,8 +780,9 @@ static void operation_sequencer(PnvSpi *s)
* transmission to the responder without requiring a refill of
* the TDR between the two operations.
*/
if (PNV_SPI_MASKED_OPCODE(s->seq_op[get_seq_index(s) + 1])
== SEQ_OP_SHIFT_N2) {
if ((seq_index != 7) &&
PNV_SPI_MASKED_OPCODE(s->seq_op[(seq_index + 1)]) ==
SEQ_OP_SHIFT_N2) {
send_n1_alone = false;
}
s->status = SETFIELD(SPI_STS_SHIFTER_FSM, s->status, FSM_SHIFT_N1);
@ -806,9 +802,8 @@ static void operation_sequencer(PnvSpi *s)
if (GETFIELD(SPI_STS_TDR_UNDERRUN, s->status)) {
s->shift_n1_done = true;
s->status = SETFIELD(SPI_STS_SHIFTER_FSM, s->status,
FSM_SHIFT_N2);
s->status = SETFIELD(SPI_STS_SEQ_INDEX, s->status,
(get_seq_index(s) + 1));
FSM_SHIFT_N2);
seq_index++;
} else {
/*
* This is case (1) or (2) so the sequencer needs to
@ -819,14 +814,16 @@ static void operation_sequencer(PnvSpi *s)
} else {
/* Ok to move on to the next index */
s->shift_n1_done = true;
next_sequencer_fsm(s);
seq_index++;
s->status = SETFIELD(SPI_STS_SEQ_FSM, s->status,
SEQ_STATE_INDEX_INCREMENT);
}
}
break;
case SEQ_OP_SHIFT_N2:
s->status = SETFIELD(SPI_STS_SEQ_FSM, s->status, SEQ_STATE_EXECUTE);
trace_pnv_spi_sequencer_op("SHIFT_N2", get_seq_index(s));
trace_pnv_spi_sequencer_op("SHIFT_N2", seq_index);
if (!s->shift_n1_done) {
qemu_log_mask(LOG_GUEST_ERROR, "Shift_N2 is not allowed if a "
"Shift_N1 is not done, shifter state = 0x%llx",
@ -851,14 +848,16 @@ static void operation_sequencer(PnvSpi *s)
s->status = SETFIELD(SPI_STS_SHIFTER_FSM, s->status, FSM_WAIT);
} else {
/* Ok to move on to the next index */
next_sequencer_fsm(s);
seq_index++;
s->status = SETFIELD(SPI_STS_SEQ_FSM, s->status,
SEQ_STATE_INDEX_INCREMENT);
}
}
break;
case SEQ_OP_BRANCH_IFNEQ_RDR:
s->status = SETFIELD(SPI_STS_SEQ_FSM, s->status, SEQ_STATE_EXECUTE);
trace_pnv_spi_sequencer_op("BRANCH_IFNEQ_RDR", get_seq_index(s));
trace_pnv_spi_sequencer_op("BRANCH_IFNEQ_RDR", seq_index);
/*
* The memory mapping register RDR match value is compared against
* the 16 rightmost bytes of the RDR (potentially with masking).
@ -874,15 +873,16 @@ static void operation_sequencer(PnvSpi *s)
if (rdr_matched) {
trace_pnv_spi_RDR_match("success");
/* A match occurred, increment the sequencer index. */
next_sequencer_fsm(s);
seq_index++;
s->status = SETFIELD(SPI_STS_SEQ_FSM, s->status,
SEQ_STATE_INDEX_INCREMENT);
} else {
trace_pnv_spi_RDR_match("failed");
/*
* Branch the sequencer to the index coded into the op
* code.
*/
s->status = SETFIELD(SPI_STS_SEQ_INDEX, s->status,
PNV_SPI_OPCODE_LO_NIBBLE(opcode));
seq_index = PNV_SPI_OPCODE_LO_NIBBLE(opcode);
}
/*
* Regardless of where the branch ended up we want the
@ -901,12 +901,13 @@ static void operation_sequencer(PnvSpi *s)
case SEQ_OP_TRANSFER_TDR:
s->status = SETFIELD(SPI_STS_SEQ_FSM, s->status, SEQ_STATE_EXECUTE);
qemu_log_mask(LOG_GUEST_ERROR, "Transfer TDR is not supported\n");
next_sequencer_fsm(s);
seq_index++;
s->status = SETFIELD(SPI_STS_SEQ_FSM, s->status, SEQ_STATE_INDEX_INCREMENT);
break;
case SEQ_OP_BRANCH_IFNEQ_INC_1:
s->status = SETFIELD(SPI_STS_SEQ_FSM, s->status, SEQ_STATE_EXECUTE);
trace_pnv_spi_sequencer_op("BRANCH_IFNEQ_INC_1", get_seq_index(s));
trace_pnv_spi_sequencer_op("BRANCH_IFNEQ_INC_1", seq_index);
/*
* The spec says the loop should execute count compare + 1 times.
* However we learned from engineering that we really only loop
@ -920,19 +921,21 @@ static void operation_sequencer(PnvSpi *s)
* mask off all but the first three bits so we don't try to
* access beyond the sequencer_operation_reg boundary.
*/
s->status = SETFIELD(SPI_STS_SEQ_INDEX, s->status,
PNV_SPI_OPCODE_LO_NIBBLE(opcode));
seq_index = PNV_SPI_OPCODE_LO_NIBBLE(opcode);
s->loop_counter_1++;
} else {
/* Continue to next index if loop counter is reached */
next_sequencer_fsm(s);
seq_index++;
s->status = SETFIELD(SPI_STS_SEQ_FSM, s->status,
SEQ_STATE_INDEX_INCREMENT);
}
break;
case SEQ_OP_BRANCH_IFNEQ_INC_2:
s->status = SETFIELD(SPI_STS_SEQ_FSM, s->status, SEQ_STATE_EXECUTE);
trace_pnv_spi_sequencer_op("BRANCH_IFNEQ_INC_2", get_seq_index(s));
uint8_t condition2 = GETFIELD(SPI_CTR_CFG_CMP2, s->regs[SPI_CTR_CFG_REG]);
trace_pnv_spi_sequencer_op("BRANCH_IFNEQ_INC_2", seq_index);
uint8_t condition2 = GETFIELD(SPI_CTR_CFG_CMP2,
s->regs[SPI_CTR_CFG_REG]);
/*
* The spec says the loop should execute count compare + 1 times.
* However we learned from engineering that we really only loop
@ -945,19 +948,21 @@ static void operation_sequencer(PnvSpi *s)
* mask off all but the first three bits so we don't try to
* access beyond the sequencer_operation_reg boundary.
*/
s->status = SETFIELD(SPI_STS_SEQ_INDEX,
s->status, PNV_SPI_OPCODE_LO_NIBBLE(opcode));
seq_index = PNV_SPI_OPCODE_LO_NIBBLE(opcode);
s->loop_counter_2++;
} else {
/* Continue to next index if loop counter is reached */
next_sequencer_fsm(s);
seq_index++;
s->status = SETFIELD(SPI_STS_SEQ_FSM, s->status,
SEQ_STATE_INDEX_INCREMENT);
}
break;
default:
s->status = SETFIELD(SPI_STS_SEQ_FSM, s->status, SEQ_STATE_EXECUTE);
/* Ignore unsupported operations. */
next_sequencer_fsm(s);
seq_index++;
s->status = SETFIELD(SPI_STS_SEQ_FSM, s->status, SEQ_STATE_INDEX_INCREMENT);
break;
} /* end of switch */
/*
@ -965,10 +970,10 @@ static void operation_sequencer(PnvSpi *s)
* we need to go ahead and end things as if there was a STOP at the
* end.
*/
if (get_seq_index(s) == NUM_SEQ_OPS) {
if (seq_index == NUM_SEQ_OPS) {
/* All 8 opcodes completed, sequencer idling */
s->status = SETFIELD(SPI_STS_SHIFTER_FSM, s->status, FSM_IDLE);
s->status = SETFIELD(SPI_STS_SEQ_INDEX, s->status, 0);
seq_index = 0;
s->loop_counter_1 = 0;
s->loop_counter_2 = 0;
s->status = SETFIELD(SPI_STS_SEQ_FSM, s->status, SEQ_STATE_IDLE);
@ -979,6 +984,8 @@ static void operation_sequencer(PnvSpi *s)
break;
}
} /* end of while */
/* Update sequencer index field in status.*/
s->status = SETFIELD(SPI_STS_SEQ_INDEX, s->status, seq_index);
return;
} /* end of operation_sequencer() */