@@ -23,6 +23,7 @@
#include "hw/ssi/ssi.h"
#include "hw/sysbus.h"
+#include "qemu/fifo8.h"
#define TYPE_PNV_SPI "pnv-spi"
OBJECT_DECLARE_SIMPLE_TYPE(PnvSpi, PNV_SPI)
@@ -37,6 +38,8 @@ typedef struct PnvSpi {
SSIBus *ssi_bus;
qemu_irq *cs_line;
MemoryRegion xscom_spic_regs;
+ Fifo8 tx_fifo;
+ Fifo8 rx_fifo;
/* SPI object number */
uint32_t spic_num;
uint8_t transfer_len;
@@ -19,6 +19,7 @@
#define PNV_SPI_OPCODE_LO_NIBBLE(x) (x & 0x0F)
#define PNV_SPI_MASKED_OPCODE(x) (x & 0xF0)
+#define PNV_SPI_FIFO_SIZE 16
/*
* Macro from include/hw/ppc/fdt.h
@@ -35,38 +36,6 @@
} \
} while (0)
-/* PnvXferBuffer */
-typedef struct PnvXferBuffer {
-
- uint32_t len;
- uint8_t *data;
-
-} PnvXferBuffer;
-
-/* pnv_spi_xfer_buffer_methods */
-static PnvXferBuffer *pnv_spi_xfer_buffer_new(void)
-{
- PnvXferBuffer *payload = g_malloc0(sizeof(*payload));
-
- return payload;
-}
-
-static void pnv_spi_xfer_buffer_free(PnvXferBuffer *payload)
-{
- free(payload->data);
- free(payload);
-}
-
-static uint8_t *pnv_spi_xfer_buffer_write_ptr(PnvXferBuffer *payload,
- uint32_t offset, uint32_t length)
-{
- if (payload->len < (offset + length)) {
- payload->len = offset + length;
- payload->data = g_realloc(payload->data, payload->len);
- }
- return &payload->data[offset];
-}
-
static bool does_rdr_match(PnvSpi *s)
{
/*
@@ -107,8 +76,8 @@ static uint8_t get_from_offset(PnvSpi *s, uint8_t offset)
return byte;
}
-static uint8_t read_from_frame(PnvSpi *s, uint8_t *read_buf, uint8_t nr_bytes,
- uint8_t ecc_count, uint8_t shift_in_count)
+static uint8_t read_from_frame(PnvSpi *s, uint8_t nr_bytes, uint8_t ecc_count,
+ uint8_t shift_in_count)
{
uint8_t byte;
int count = 0;
@@ -118,8 +87,8 @@ static uint8_t read_from_frame(PnvSpi *s, uint8_t *read_buf, uint8_t nr_bytes,
if ((ecc_count != 0) &&
(shift_in_count == (PNV_SPI_REG_SIZE + ecc_count))) {
shift_in_count = 0;
- } else {
- byte = read_buf[count];
+ } else if (!fifo8_is_empty(&s->rx_fifo)) {
+ byte = fifo8_pop(&s->rx_fifo);
trace_pnv_spi_shift_rx(byte, count);
s->regs[SPI_RCV_DATA_REG] = (s->regs[SPI_RCV_DATA_REG] << 8) | byte;
}
@@ -128,7 +97,7 @@ static uint8_t read_from_frame(PnvSpi *s, uint8_t *read_buf, uint8_t nr_bytes,
return shift_in_count;
}
-static void spi_response(PnvSpi *s, int bits, PnvXferBuffer *rsp_payload)
+static void spi_response(PnvSpi *s)
{
uint8_t ecc_count;
uint8_t shift_in_count;
@@ -144,13 +113,13 @@ static void spi_response(PnvSpi *s, int bits, PnvXferBuffer *rsp_payload)
* First check that the response payload is the exact same
* number of bytes as the request payload was
*/
- if (rsp_payload->len != (s->N1_bytes + s->N2_bytes)) {
+ if ((&s->rx_fifo)->num != (s->N1_bytes + s->N2_bytes)) {
qemu_log_mask(LOG_GUEST_ERROR, "Invalid response payload size in "
"bytes, expected %d, got %d\n",
- (s->N1_bytes + s->N2_bytes), rsp_payload->len);
+ (s->N1_bytes + s->N2_bytes), (&s->rx_fifo)->num);
} else {
uint8_t ecc_control;
- trace_pnv_spi_rx_received(rsp_payload->len);
+ trace_pnv_spi_rx_received((&s->rx_fifo)->num);
trace_pnv_spi_log_Ncounts(s->N1_bits, s->N1_bytes, s->N1_tx,
s->N1_rx, s->N2_bits, s->N2_bytes, s->N2_tx, s->N2_rx);
/*
@@ -175,14 +144,13 @@ static void spi_response(PnvSpi *s, int bits, PnvXferBuffer *rsp_payload)
/* Handle the N1 portion of the frame first */
if (s->N1_rx != 0) {
trace_pnv_spi_rx_read_N1frame();
- shift_in_count = read_from_frame(s, &rsp_payload->data[0],
- s->N1_bytes, ecc_count, shift_in_count);
+ shift_in_count = read_from_frame(s, s->N1_bytes,
+ ecc_count, shift_in_count);
}
/* Handle the N2 portion of the frame */
if (s->N2_rx != 0) {
trace_pnv_spi_rx_read_N2frame();
- shift_in_count = read_from_frame(s,
- &rsp_payload->data[s->N1_bytes], s->N2_bytes,
+ shift_in_count = read_from_frame(s, s->N2_bytes,
ecc_count, shift_in_count);
}
if ((s->N1_rx + s->N2_rx) > 0) {
@@ -210,34 +178,36 @@ static void spi_response(PnvSpi *s, int bits, PnvXferBuffer *rsp_payload)
} /* end of else */
} /* end of spi_response() */
-static void transfer(PnvSpi *s, PnvXferBuffer *payload)
+static void transfer(PnvSpi *s)
{
- uint32_t tx;
- uint32_t rx;
- PnvXferBuffer *rsp_payload = NULL;
+ uint32_t tx, rx, payload_len;
+ uint8_t rx_byte;
- rsp_payload = pnv_spi_xfer_buffer_new();
- for (int offset = 0; offset < payload->len; offset += s->transfer_len) {
+ payload_len = (&s->tx_fifo)->num;
+ for (int offset = 0; offset < payload_len; offset += s->transfer_len) {
tx = 0;
for (int i = 0; i < s->transfer_len; i++) {
- if ((offset + i) >= payload->len) {
+ if ((offset + i) >= payload_len) {
tx <<= 8;
- } else {
- tx = (tx << 8) | payload->data[offset + i];
+ } else if (!fifo8_is_empty(&s->tx_fifo)) {
+ tx = (tx << 8) | fifo8_pop(&s->tx_fifo);
}
}
rx = ssi_transfer(s->ssi_bus, tx);
for (int i = 0; i < s->transfer_len; i++) {
- if ((offset + i) >= payload->len) {
+ if ((offset + i) >= payload_len) {
break;
}
- *(pnv_spi_xfer_buffer_write_ptr(rsp_payload, rsp_payload->len, 1)) =
- (rx >> (8 * (s->transfer_len - 1) - i * 8)) & 0xFF;
+ rx_byte = (rx >> (8 * (s->transfer_len - 1) - i * 8)) & 0xFF;
+ if (!fifo8_is_full(&s->rx_fifo)) {
+ fifo8_push(&s->rx_fifo, rx_byte);
+ }
}
}
- if (rsp_payload != NULL) {
- spi_response(s, s->N1_bits, rsp_payload);
- }
+ spi_response(s);
+ /* Reset fifo for next frame */
+ fifo8_reset(&s->tx_fifo);
+ fifo8_reset(&s->rx_fifo);
}
static inline uint8_t get_seq_index(PnvSpi *s)
@@ -348,19 +318,10 @@ static void calculate_N1(PnvSpi *s, uint8_t opcode)
/*
* Shift_N1 operation handler method
*/
-static bool operation_shiftn1(PnvSpi *s, uint8_t opcode,
- PnvXferBuffer **payload, bool send_n1_alone)
+static bool operation_shiftn1(PnvSpi *s, uint8_t opcode, bool send_n1_alone)
{
uint8_t n1_count;
bool stop = false;
-
- /*
- * If there isn't a current payload left over from a stopped sequence
- * create a new one.
- */
- if (*payload == NULL) {
- *payload = pnv_spi_xfer_buffer_new();
- }
/*
* Use a combination of N1 counters to build the N1 portion of the
* transmit payload.
@@ -411,9 +372,10 @@ static bool operation_shiftn1(PnvSpi *s, uint8_t opcode,
*/
uint8_t n1_byte = 0x00;
n1_byte = get_from_offset(s, n1_count);
- trace_pnv_spi_tx_append("n1_byte", n1_byte, n1_count);
- *(pnv_spi_xfer_buffer_write_ptr(*payload, (*payload)->len, 1)) =
- n1_byte;
+ if (!fifo8_is_full(&s->tx_fifo)) {
+ trace_pnv_spi_tx_append("n1_byte", n1_byte, n1_count);
+ fifo8_push(&s->tx_fifo, n1_byte);
+ }
} else {
/*
* We hit a shift_n1 opcode TX but the TDR is empty, tell the
@@ -440,10 +402,9 @@ static bool operation_shiftn1(PnvSpi *s, uint8_t opcode,
"set for receive but RDR is full");
stop = true;
break;
- } else {
+ } else if (!fifo8_is_full(&s->tx_fifo)) {
trace_pnv_spi_tx_append_FF("n1_byte");
- *(pnv_spi_xfer_buffer_write_ptr(*payload, (*payload)->len, 1))
- = 0xff;
+ fifo8_push(&s->tx_fifo, 0xff);
}
}
n1_count++;
@@ -484,15 +445,13 @@ static bool operation_shiftn1(PnvSpi *s, uint8_t opcode,
*/
if (send_n1_alone && !stop) {
/* We have a TX and a full TDR or an RX and an empty RDR */
- trace_pnv_spi_tx_request("Shifting N1 frame", (*payload)->len);
- transfer(s, *payload);
+ trace_pnv_spi_tx_request("Shifting N1 frame", (&s->tx_fifo)->num);
+ transfer(s);
/* The N1 frame shift is complete so reset the N1 counters */
s->N2_bits = 0;
s->N2_bytes = 0;
s->N2_tx = 0;
s->N2_rx = 0;
- pnv_spi_xfer_buffer_free(*payload);
- *payload = NULL;
}
return stop;
} /* end of operation_shiftn1() */
@@ -588,19 +547,10 @@ static void calculate_N2(PnvSpi *s, uint8_t opcode)
* Shift_N2 operation handler method
*/
-static bool operation_shiftn2(PnvSpi *s, uint8_t opcode,
- PnvXferBuffer **payload)
+static bool operation_shiftn2(PnvSpi *s, uint8_t opcode)
{
uint8_t n2_count;
bool stop = false;
-
- /*
- * If there isn't a current payload left over from a stopped sequence
- * create a new one.
- */
- if (*payload == NULL) {
- *payload = pnv_spi_xfer_buffer_new();
- }
/*
* Use a combination of N2 counters to build the N2 portion of the
* transmit payload.
@@ -639,25 +589,26 @@ static bool operation_shiftn2(PnvSpi *s, uint8_t opcode,
/* Always append data for the N2 segment if it is set for TX */
uint8_t n2_byte = 0x00;
n2_byte = get_from_offset(s, (s->N1_tx + n2_count));
- trace_pnv_spi_tx_append("n2_byte", n2_byte, (s->N1_tx + n2_count));
- *(pnv_spi_xfer_buffer_write_ptr(*payload, (*payload)->len, 1))
- = n2_byte;
- } else {
+ if (!fifo8_is_full(&s->tx_fifo)) {
+ trace_pnv_spi_tx_append("n2_byte", n2_byte,
+ (s->N1_tx + n2_count));
+ fifo8_push(&s->tx_fifo, n2_byte);
+ }
+ } else if (!fifo8_is_full(&s->tx_fifo)) {
/*
* Regardless of whether or not N2 is set for TX or RX, we need
* the number of bytes in the payload to match the overall length
* of the operation.
*/
trace_pnv_spi_tx_append_FF("n2_byte");
- *(pnv_spi_xfer_buffer_write_ptr(*payload, (*payload)->len, 1))
- = 0xff;
+ fifo8_push(&s->tx_fifo, 0xff);
}
n2_count++;
} /* end of while */
if (!stop) {
/* We have a TX and a full TDR or an RX and an empty RDR */
- trace_pnv_spi_tx_request("Shifting N2 frame", (*payload)->len);
- transfer(s, *payload);
+ trace_pnv_spi_tx_request("Shifting N2 frame", (&s->tx_fifo)->num);
+ transfer(s);
/*
* If we are doing an N2 TX and the TDR is full we need to clear the
* TDR_full status. Do this here instead of up in the loop above so we
@@ -680,8 +631,6 @@ static bool operation_shiftn2(PnvSpi *s, uint8_t opcode,
s->N1_bytes = 0;
s->N1_tx = 0;
s->N1_rx = 0;
- pnv_spi_xfer_buffer_free(*payload);
- *payload = NULL;
}
return stop;
} /* end of operation_shiftn2()*/
@@ -699,19 +648,6 @@ static void operation_sequencer(PnvSpi *s)
uint8_t opcode = 0;
uint8_t masked_opcode = 0;
- /*
- * PnvXferBuffer for containing the payload of the SPI frame.
- * This is a static because there are cases where a sequence has to stop
- * and wait for the target application to unload the RDR. If this occurs
- * during a sequence where N1 is not sent alone and instead combined with
- * N2 since the N1 tx length + the N2 tx length is less than the size of
- * the TDR.
- */
- static PnvXferBuffer *payload;
-
- if (payload == NULL) {
- payload = pnv_spi_xfer_buffer_new();
- }
/*
* Clear the sequencer FSM error bit - general_SPI_status[3]
* before starting a sequence.
@@ -840,7 +776,7 @@ static void operation_sequencer(PnvSpi *s)
}
s->status = SETFIELD(SPI_STS_SHIFTER_FSM, s->status,
FSM_SHIFT_N1);
- stop = operation_shiftn1(s, opcode, &payload, send_n1_alone);
+ stop = operation_shiftn1(s, opcode, send_n1_alone);
if (stop) {
/*
* The operation code says to stop, this can occur if:
@@ -895,7 +831,7 @@ static void operation_sequencer(PnvSpi *s)
/* Ok to do a Shift_N2 */
s->status = SETFIELD(SPI_STS_SHIFTER_FSM, s->status,
FSM_SHIFT_N2);
- stop = operation_shiftn2(s, opcode, &payload);
+ stop = operation_shiftn2(s, opcode);
/*
* If the operation code says to stop set the shifter state to
* wait and stop
@@ -1208,6 +1144,9 @@ static void pnv_spi_realize(DeviceState *dev, Error **errp)
s->cs_line = g_new0(qemu_irq, 1);
qdev_init_gpio_out_named(DEVICE(s), s->cs_line, "cs", 1);
+ fifo8_create(&s->tx_fifo, PNV_SPI_FIFO_SIZE);
+ fifo8_create(&s->rx_fifo, PNV_SPI_FIFO_SIZE);
+
/* spi scoms */
pnv_xscom_region_init(&s->xscom_spic_regs, OBJECT(s), &pnv_spi_xscom_ops,
s, "xscom-spi", PNV10_XSCOM_PIB_SPIC_SIZE);
In PnvXferBuffer dynamically allocating and freeing is a process overhead. Hence used an existing Fifo8 buffer with capacity of 16 bytes. Signed-off-by: Chalapathi V <chalapathi.v@linux.ibm.com> --- include/hw/ssi/pnv_spi.h | 3 + hw/ssi/pnv_spi.c | 167 +++++++++++++-------------------------- 2 files changed, 56 insertions(+), 114 deletions(-)