applications: sdp: mspi: Fixed additional clock edge in modes 1-3

Added workarounds to hardware issue causing,
additional clock edge in spi modes 1-3.

Signed-off-by: Michal Frankiewicz <[email protected]>

Author: mif1-nordic

applications/sdp/mspi/src/hrt/hrt-nrf54l15.s

@@ -289,7 +289,7 @@ hrt_write:
 	beq	a3,a2,.L40
 	li	a5,32
 	div	a5,a5,a4
-	j	.L57
+	j	.L56
 .L36:
 	lbu	a4,81(s0)
 	j	.L38
@@ -298,14 +298,14 @@ hrt_write:
 	j	.L38
 .L39:
 	lbu	a5,8(a5)
-.L57:
+.L56:
  #APP
 	csrw 3022, a5
  #NO_APP
-	lbu	a4,86(s0)
+	lbu	a4,87(s0)
 	li	a5,1
 	sll	a5,a5,a4
-	lbu	a4,88(s0)
+	lbu	a4,89(s0)
 	slli	a5,a5,16
 	srli	a5,a5,16
 	bne	a4,zero,.L43
@@ -333,34 +333,28 @@ hrt_write:
 	addi	a2,sp,3
 	addi	a0,s0,60
 	call	hrt_tx
-	lbu	a5,89(s0)
-	beq	a5,zero,.L45
-.L46:
- #APP
-	csrr a5, 3022
- #NO_APP
-	andi	a5,a5,0xff
-	bne	a5,zero,.L46
- #APP
-	csrw 2010, 0
- #NO_APP
-.L45:
+	lbu	a5,94(s0)
+	bne	a5,zero,.L45
 	li	a5,16384
 	addi	a5,a5,1
  #APP
 	csrw 3019, a5
 	csrw 3017, 0
 	csrw 2000, 0
  #NO_APP
-	lbu	a5,87(s0)
+.L46:
+ #APP
+	csrw 2005, 0
+ #NO_APP
+	lbu	a5,88(s0)
 	bne	a5,zero,.L33
-	lbu	a4,86(s0)
+	lbu	a4,87(s0)
 	li	a5,1
 	sll	a5,a5,a4
-	lbu	a4,88(s0)
+	lbu	a4,89(s0)
 	slli	a5,a5,16
 	srli	a5,a5,16
-	bne	a4,zero,.L48
+	bne	a4,zero,.L49
  #APP
 	csrs 3008, a5
  #NO_APP
@@ -371,13 +365,49 @@ hrt_write:
 	jr	ra
 .L40:
 	lbu	a5,9(a5)
-	j	.L57
+	j	.L56
 .L43:
  #APP
 	csrs 3008, a5
  #NO_APP
 	j	.L44
-.L48:
+.L45:
+ #APP
+	csrr a5, 3022
+ #NO_APP
+	andi	a5,a5,0xff
+	bne	a5,zero,.L45
+ #APP
+	csrw 2000, 0
+ #NO_APP
+	li	a5,16384
+	addi	a5,a5,1
+ #APP
+	csrw 3019, a5
+ #NO_APP
+	lbu	a5,94(s0)
+	li	a4,1
+	bne	a5,a4,.L47
+	lbu	a4,86(s0)
+	sll	a5,a5,a4
+	slli	a5,a5,16
+	srli	a5,a5,16
+ #APP
+	csrc 3008, a5
+ #NO_APP
+	j	.L46
+.L47:
+	li	a3,3
+	bne	a5,a3,.L46
+	lbu	a5,86(s0)
+	sll	a4,a4,a5
+	slli	a4,a4,16
+	srli	a4,a4,16
+ #APP
+	csrs 3008, a4
+ #NO_APP
+	j	.L46
+.L49:
  #APP
 	csrc 3008, a5
  #NO_APP
@@ -391,18 +421,18 @@ hrt_read:
 	addi	sp,sp,-12
 	sw	s0,4(sp)
 	sw	ra,8(sp)
-	lbu	a5,88(a0)
-	lbu	a4,86(a0)
+	lbu	a5,89(a0)
+	lbu	a4,87(a0)
 	mv	s0,a0
-	bne	a5,zero,.L59
+	bne	a5,zero,.L58
 	li	a5,1
 	sll	a5,a5,a4
 	slli	a5,a5,16
 	srli	a5,a5,16
  #APP
 	csrc 3008, a5
  #NO_APP
-.L60:
+.L59:
 	lhu	a5,90(s0)
 	slli	a5,a5,16
 	srli	a5,a5,16
@@ -461,27 +491,27 @@ hrt_read:
 	addi	a0,s0,20
 	call	hrt_tx_rx.constprop.0
 	li	a5,0
-.L61:
+.L60:
 	lw	a4,64(s0)
-	bltu	a5,a4,.L62
+	bltu	a5,a4,.L61
  #APP
 	csrw 2000, 0
 	csrw 2001, 0
 	csrw 3019, 0
  #NO_APP
-	lbu	a5,87(s0)
-	bne	a5,zero,.L63
 	lbu	a5,88(s0)
-	lbu	a4,86(s0)
-	bne	a5,zero,.L64
+	bne	a5,zero,.L62
+	lbu	a5,89(s0)
+	lbu	a4,87(s0)
+	bne	a5,zero,.L63
 	li	a5,1
 	sll	a5,a5,a4
 	slli	a5,a5,16
 	srli	a5,a5,16
  #APP
 	csrs 3008, a5
  #NO_APP
-.L63:
+.L62:
 	lhu	a5,90(s0)
 	ori	a5,a5,4
 	sh	a5,90(s0)
@@ -493,16 +523,16 @@ hrt_read:
 	lw	s0,4(sp)
 	addi	sp,sp,12
 	jr	ra
-.L59:
+.L58:
 	li	a5,1
 	sll	a5,a5,a4
 	slli	a5,a5,16
 	srli	a5,a5,16
  #APP
 	csrs 3008, a5
  #NO_APP
-	j	.L60
-.L62:
+	j	.L59
+.L61:
  #APP
 	csrr a3, 3018
  #NO_APP
@@ -512,16 +542,16 @@ hrt_read:
 	addi	a5,a5,1
 	sb	a3,0(a4)
 	andi	a5,a5,0xff
-	j	.L61
-.L64:
+	j	.L60
+.L63:
 	li	a5,1
 	sll	a5,a5,a4
 	slli	a5,a5,16
 	srli	a5,a5,16
  #APP
 	csrc 3008, a5
  #NO_APP
-	j	.L63
+	j	.L62
 	.size	hrt_read, .-hrt_read
 	.section	.sdata.xfer_shift_ctrl,"aw"
 	.align	2

applications/sdp/mspi/src/hrt/hrt.c

@@ -213,24 +213,32 @@ void hrt_write(hrt_xfer_t *hrt_xfer_params)
 	hrt_tx(&hrt_xfer_params->xfer_data[HRT_FE_DATA], hrt_xfer_params->bus_widths.data,
 	       &counter_running, hrt_xfer_params->counter_value);
 
-	if (hrt_xfer_params->eliminate_last_pulse) {
-
-		/* Wait until the last word is sent */
+	/* Hardware issue workaround,
+	 * additional clock edge when transmitting in modes other than MSPI_CPP_MODE_0.
+	 * modes 1 and 3: Disable clock before the last pulse and perform last clock edge manualy.
+	 * mode 2: Add one pulse more to the last word in message, and disable clock before the last
+	 * pulse.
+	 */
+	if (hrt_xfer_params->cpp_mode == MSPI_CPP_MODE_0) {
+		nrf_vpr_csr_vio_shift_ctrl_buffered_set(&write_final_shift_ctrl_cfg);
+		nrf_vpr_csr_vio_out_buffered_reversed_word_set(0x00);
+		nrf_vpr_csr_vtim_count_mode_set(0, NRF_VPR_CSR_VTIM_COUNT_STOP);
+	} else {
 		while (nrf_vpr_csr_vio_shift_cnt_out_get() != 0) {
 		}
+		nrf_vpr_csr_vtim_count_mode_set(0, NRF_VPR_CSR_VTIM_COUNT_STOP);
 
-		/* This is a partial solution to surplus clock edge problem in modes 1 and 3.
-		 * This solution works only for counter values above 20.
-		 */
-		nrf_vpr_csr_vtim_simple_wait_set(0, false, 0);
-	}
+		nrf_vpr_csr_vio_shift_ctrl_buffered_set(&write_final_shift_ctrl_cfg);
 
-	/* Final configuration */
-	nrf_vpr_csr_vio_shift_ctrl_buffered_set(&write_final_shift_ctrl_cfg);
-	nrf_vpr_csr_vio_out_buffered_reversed_word_set(0x00);
+		if (hrt_xfer_params->cpp_mode == MSPI_CPP_MODE_1) {
+			nrf_vpr_csr_vio_out_clear_set(BIT(hrt_xfer_params->clk_vio));
+		} else if (hrt_xfer_params->cpp_mode == MSPI_CPP_MODE_3) {
+			nrf_vpr_csr_vio_out_or_set(BIT(hrt_xfer_params->clk_vio));
+		}
+	}
 
-	/* Stop counter */
-	nrf_vpr_csr_vtim_count_mode_set(0, NRF_VPR_CSR_VTIM_COUNT_STOP);
+	/* Reset counter 0, Next message may be sent incorrectly if counter is not reset here. */
+	nrf_vpr_csr_vtim_simple_counter_set(0, 0);
 
 	/* Disable CE */
 	if (!hrt_xfer_params->ce_hold) {

applications/sdp/mspi/src/hrt/hrt.h

@@ -89,6 +89,9 @@ typedef struct {
 	 */
 	uint16_t counter_value;
 
+	/** @brief Index of clock VIO pin */
+	uint8_t clk_vio;
+
 	/** @brief Index of CE VIO pin */
 	uint8_t ce_vio;
 
@@ -98,17 +101,15 @@ typedef struct {
 	/** @brief Chip enable pin polarity in enabled state. */
 	enum mspi_ce_polarity ce_polarity;
 
-	/** @brief When true clock signal makes 1 transition less.
-	 *         It is required for spi modes 1 and 3 due to hardware issue.
-	 */
-	bool eliminate_last_pulse;
-
 	/** @brief Tx mode mask for csr dir register  */
 	uint16_t tx_direction_mask;
 
 	/** @brief Rx mode mask for csr dir register  */
 	uint16_t rx_direction_mask;
 
+	/** @brief Due to hardware issues hrt module needs to know about selected spi mode */
+	enum mspi_cpp_mode cpp_mode;
+
 } hrt_xfer_t;
 
 /** @brief Write.

applications/sdp/mspi/src/main.c

@@ -152,25 +152,21 @@ static void configure_clock(enum mspi_cpp_mode cpp_mode)
 	case MSPI_CPP_MODE_0: {
 		vio_config.clk_polarity = 0;
 		WRITE_BIT(out, pin_to_vio_map[NRFE_MSPI_SCK_PIN_NUMBER], VPRCSR_NORDIC_OUT_LOW);
-		xfer_params.eliminate_last_pulse = false;
 		break;
 	}
 	case MSPI_CPP_MODE_1: {
 		vio_config.clk_polarity = 1;
 		WRITE_BIT(out, pin_to_vio_map[NRFE_MSPI_SCK_PIN_NUMBER], VPRCSR_NORDIC_OUT_LOW);
-		xfer_params.eliminate_last_pulse = true;
 		break;
 	}
 	case MSPI_CPP_MODE_2: {
 		vio_config.clk_polarity = 1;
 		WRITE_BIT(out, pin_to_vio_map[NRFE_MSPI_SCK_PIN_NUMBER], VPRCSR_NORDIC_OUT_HIGH);
-		xfer_params.eliminate_last_pulse = false;
 		break;
 	}
 	case MSPI_CPP_MODE_3: {
 		vio_config.clk_polarity = 0;
 		WRITE_BIT(out, pin_to_vio_map[NRFE_MSPI_SCK_PIN_NUMBER], VPRCSR_NORDIC_OUT_HIGH);
-		xfer_params.eliminate_last_pulse = true;
 		break;
 	}
 	}
@@ -190,8 +186,10 @@ static void xfer_execute(nrfe_mspi_xfer_packet_msg_t *xfer_packet)
 	xfer_params.counter_value = 4;
 	xfer_params.ce_vio = ce_vios[device->ce_index];
 	xfer_params.ce_hold = nrfe_mspi_xfer_config.hold_ce;
+	xfer_params.cpp_mode = device->cpp;
 	xfer_params.ce_polarity = device->ce_polarity;
 	xfer_params.bus_widths = io_modes[device->io_mode];
+	xfer_params.clk_vio = pin_to_vio_map[NRFE_MSPI_SCK_PIN_NUMBER];
 
 	/* Fix position of command and address if command/address length is < BITS_IN_WORD,
 	 * so that leading zeros would not be printed instead of data bits.
@@ -248,6 +246,21 @@ static void xfer_execute(nrfe_mspi_xfer_packet_msg_t *xfer_packet)
 	adjust_tail(&xfer_params.xfer_data[HRT_FE_DATA], xfer_params.bus_widths.data,
 		    xfer_packet->num_bytes * BITS_IN_BYTE);
 
+	/* Hardware issue: Additional clock edge when transmitting in modes other
+	 *                 than MSPI_CPP_MODE_0.
+	 * Here is first part workaround of that issue only for MSPI_CPP_MODE_2.
+	 * Workaround: Add one pulse more to the last word in message,
+	 *             and disable clock before the last pulse.
+	 */
+	if (device->cpp == MSPI_CPP_MODE_2) {
+		for (uint8_t i = 0; i < HRT_FE_MAX; i++) {
+			if (xfer_params.xfer_data[HRT_FE_MAX - 1 - i].word_count != 0) {
+				xfer_params.xfer_data[HRT_FE_MAX - 1 - i].last_word_clocks++;
+				break;
+			}
+		}
+	}
+
 	nrf_vpr_clic_int_pending_set(NRF_VPRCLIC, VEVIF_IRQN(HRT_VEVIF_IDX_WRITE));
 }