icE1usb fw: Update E1 core start/stop procedure
Previously we were just doing a hard reset, calling init again.
And to stop, it was a bit harsh as well, just calling init with
0 as argument, not cleaning pending descriptors and such.
Now, the HW is initialized once and there is proper startup and
shutdown procedure, leaving things in the proper state.
Init of e1 hardware (call to e1_init) is also delegated to usb_e1
since it's that module that handles all state changes and config
so it makes sense it handles init too rather than calling it from
fw_app.c
Signed-off-by: Sylvain Munaut <tnt@246tNt.com>
Change-Id: I639f90ce3488a1a08e87854e74e0586010264f5d
diff --git a/firmware/ice40-riscv/icE1usb/e1.c b/firmware/ice40-riscv/icE1usb/e1.c
index 964b0bc..b1695a6 100644
--- a/firmware/ice40-riscv/icE1usb/e1.c
+++ b/firmware/ice40-riscv/icE1usb/e1.c
@@ -226,10 +226,11 @@
// ----------
enum e1_pipe_state {
- IDLE = 0, /* not yet initialized */
- BOOT = 1, /* after e1_init(), regiters are programmed */
- RUN = 2, /* normal operation */
- RECOVER = 3, /* after underflow, overflow or alignment error */
+ IDLE = 0, /* not running */
+ STARTING = 1, /* after e1_start(), waiting for priming */
+ RUN = 2, /* normal operation */
+ RECOVER = 3, /* after underflow, overflow or alignment error */
+ SHUTDOWN = 4, /* after e1_stop(), waiting for shutdown */
};
struct e1_state {
@@ -324,8 +325,8 @@
e1f_init(&e1->tx.fifo, (512 * port) + 256, 256);
/* Flow state */
- e1->rx.state = BOOT;
- e1->tx.state = BOOT;
+ e1->rx.state = IDLE;
+ e1->tx.state = IDLE;
/* Set config registers */
e1->rx.cr.cfg = rx_cr & RXCR_PERMITTED;
@@ -357,6 +358,48 @@
e1_regs->tx.csr = e1->tx.cr.val;
}
+void
+e1_start(int port)
+{
+ volatile struct e1_core *e1_regs = _get_regs(port);
+ struct e1_state *e1 = _get_state(port);
+
+ /* Checks */
+ while ((e1->rx.state == SHUTDOWN) || (e1->tx.state == SHUTDOWN))
+ e1_poll(port);
+
+ if ((e1->rx.state != IDLE) || (e1->tx.state != IDLE))
+ panic("Invalid E1 hardware state (port=%d, rxs=%d, txs=%d)",
+ port, e1->rx.state, e1->tx.state);
+
+ /* Clear FIFOs */
+ e1f_reset(&e1->rx.fifo);
+ e1f_reset(&e1->tx.fifo);
+
+ /* Flow state */
+ e1->rx.state = STARTING;
+ e1->tx.state = STARTING;
+
+ /* Update CRs */
+ _e1_update_cr_val(port);
+
+ e1_regs->rx.csr = e1->rx.cr.val | E1_RX_CR_OVFL_CLR;
+ e1_regs->tx.csr = e1->tx.cr.val | E1_TX_CR_UNFL_CLR;
+}
+
+void
+e1_stop(int port)
+{
+ struct e1_state *e1 = _get_state(port);
+
+ /* Flow state */
+ e1->rx.state = SHUTDOWN;
+ e1->tx.state = SHUTDOWN;
+
+ /* Nothing else to do, e1_poll will stop submitting data and
+ * transition to IDLE when everything in-flight is done */
+}
+
unsigned int
e1_rx_need_data(int port, unsigned int usb_addr, unsigned int max_frames, unsigned int *pos)
{
@@ -512,7 +555,7 @@
}
/* Boot procedure */
- if (e1->tx.state == BOOT) {
+ if (e1->tx.state == STARTING) {
if (e1f_unseen_frames(&e1->tx.fifo) < (16 * 5))
return;
/* HACK: LED flow status */
@@ -521,6 +564,20 @@
}
/* Handle RX */
+ /* Bypass if OFF */
+ if (e1->rx.state == IDLE)
+ goto done_rx;
+
+ /* Shutdown */
+ if (e1->rx.state == SHUTDOWN) {
+ if (e1->rx.in_flight == 0) {
+ e1->rx.state = IDLE;
+ _e1_update_cr_val(port);
+ e1_regs->rx.csr = e1->rx.cr.val;
+ }
+ goto done_rx;
+ }
+
/* Misalign ? */
if (e1->rx.state == RUN) {
if (!(e1_regs->rx.csr & E1_RX_SR_ALIGNED)) {
@@ -562,6 +619,20 @@
done_rx:
/* Handle TX */
+ /* Bypass if OFF */
+ if (e1->tx.state == IDLE)
+ return;
+
+ /* Shutdown */
+ if (e1->tx.state == SHUTDOWN) {
+ if (e1->tx.in_flight == 0) {
+ e1->tx.state = IDLE;
+ _e1_update_cr_val(port);
+ e1_regs->tx.csr = e1->tx.cr.val;
+ }
+ return;
+ }
+
/* Underflow ? */
if (e1->tx.state == RUN) {
if (e1_regs->tx.csr & E1_TX_SR_UNFL) {