1 files changed, 209 insertions, 0 deletions
diff --git a/src/soc/sifive/fu740/spi.c b/src/soc/sifive/fu740/spi.c
new file mode 100644
index 0000000000..908e6ca476
--- /dev/null
+++ b/src/soc/sifive/fu740/spi.c
@@ -0,0 +1,209 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+//TODO needs work
+
+#include <device/mmio.h>
+#include <soc/spi.h>
+#include <soc/clock.h>
+#include <soc/addressmap.h>
+#include <delay.h>
+#include <lib.h>
+
+#include "spi_internal.h"
+
+static struct fu740_spi_ctrl *fu740_spi_ctrls[] = {
+	(struct fu740_spi_ctrl *)FU740_QSPI0,
+	(struct fu740_spi_ctrl *)FU740_QSPI1,
+	(struct fu740_spi_ctrl *)FU740_QSPI2
+};
+
+// Wait until SPI is ready for transmission and transmit byte.
+static void fu740_spi_tx(volatile struct fu740_spi_ctrl *spictrl_reg, uint8_t in)
+{
+#if __riscv_atomic
+	int32_t r;
+	do {
+		asm volatile (
+			"amoor.w %0, %2, %1\n"
+			: "=r" (r), "+A" (spictrl_reg->txdata.raw_bits)
+			: "r" (in)
+		);
+	} while (r < 0);
+#else
+	while ((int32_t) spictrl_reg->txdata.raw_bits < 0)
+		;
+	spictrl_reg->txdata.data = in;
+#endif
+}
+
+// Wait until SPI receive queue has data and read byte.
+static uint8_t fu740_spi_rx(volatile struct fu740_spi_ctrl *spictrl_reg)
+{
+	int32_t out;
+	while ((out = (int32_t) spictrl_reg->rxdata.raw_bits) < 0)
+		;
+	return (uint8_t) out;
+}
+
+static int fu740_spi_xfer(const struct spi_slave *slave,
+			  const void *dout, size_t bytesout,
+			  void *din, size_t bytesin)
+{
+	printk(BIOS_DEBUG, "%s 0, bytesin: %zu, bytesout: %zu, din: %p\n", __func__, bytesin, bytesout, din);
+	hexdump(dout, bytesout);
+	struct fu740_spi_ctrl *spictrl_reg = fu740_spi_ctrls[slave->bus];
+	union fu740_spi_reg_fmt fmt;
+	fmt.raw_bits = read32(&spictrl_reg->fmt.raw_bits);
+	if (fmt.proto == FU740_SPI_PROTO_S) {
+		// working in full-duplex mode
+		// receiving data needs to be triggered by sending data
+		while (bytesout || bytesin) {
+			uint8_t in, out = 0;
+			if (bytesout) {
+				out = *(uint8_t *)dout++;
+				bytesout--;
+			}
+			fu740_spi_tx(spictrl_reg, out);
+			in = fu740_spi_rx(spictrl_reg);
+			if (bytesin) {
+				*(uint8_t *)din++ = in;
+				bytesin--;
+			}
+		}
+	} else {
+		// Working in half duplex
+		// send and receive can be done separately
+		if (dout && din)
+			return -1;
+
+		if (dout) {
+			while (bytesout) {
+				fu740_spi_tx(spictrl_reg, *(uint8_t *)dout++);
+				bytesout--;
+			}
+		}
+
+		if (din) {
+			while (bytesin) {
+				*(uint8_t *)din++ = fu740_spi_rx(spictrl_reg);
+				bytesin--;
+			}
+		}
+	}
+	return 0;
+}
+
+static int fu740_spi_claim_bus(const struct spi_slave *slave)
+{
+	struct fu740_spi_ctrl *spictrl = fu740_spi_ctrls[slave->bus];
+	union fu740_spi_reg_csmode csmode;
+	csmode.raw_bits = 0;
+	csmode.mode = FU740_SPI_CSMODE_HOLD;
+	write32(&spictrl->csmode.raw_bits, csmode.raw_bits);
+	return 0;
+}
+
+static void fu740_spi_release_bus(const struct spi_slave *slave)
+{
+	struct fu740_spi_ctrl *spictrl = fu740_spi_ctrls[slave->bus];
+	union fu740_spi_reg_csmode csmode;
+	csmode.raw_bits = 0;
+	csmode.mode = FU740_SPI_CSMODE_OFF;
+	write32(&spictrl->csmode.raw_bits, csmode.raw_bits);
+}
+
+// reset spi flash chip
+static void fu740_spi_reset(volatile struct fu740_spi_ctrl *spictrl_reg)
+{
+	fu740_spi_tx(spictrl_reg, 0x66);
+	fu740_spi_tx(spictrl_reg, 0x99);
+}
+
+// setup the ffmt (SPI flash instruction format) register
+__maybe_unused static int fu740_spi_setup_ffmt(volatile struct fu740_spi_ctrl *spictrl_reg,
+			 const struct fu740_spi_config *config)
+{
+	//union fu740_spi_reg_fctrl fctrl;
+	union fu740_spi_reg_ffmt ffmt;
+
+	printk(BIOS_DEBUG, "config->data_proto: %d, config->cmd_code: %d\n",
+			config->ffmt_config.data_proto,
+			config->ffmt_config.cmd_code);
+
+	//TODO test without this here
+	fu740_spi_reset(spictrl_reg);
+
+	ffmt.raw_bits   = 0;
+	ffmt.cmd_en     = 1; // enable sending of command
+	ffmt.addr_len   = 3; // number of address bytes (0-4)
+	ffmt.pad_cnt    = 0; // number of dummy cycles TODO maybe not working
+	ffmt.cmd_proto  = FU740_SPI_PROTO_S; // protocol for transmitting command
+	ffmt.addr_proto = FU740_SPI_PROTO_S; // protocol for transmitting address and padding
+	ffmt.data_proto = config->ffmt_config.data_proto; // protocol for receiving data bytes
+	ffmt.cmd_code   = config->ffmt_config.cmd_code;   // value of command byte
+	ffmt.pad_code   = 0; // First 8 bits to transmit during dummy cycles
+	write32(&spictrl_reg->ffmt.raw_bits, ffmt.raw_bits);
+
+	return 0;
+}
+
+int fu740_spi_setup(const struct spi_slave *slave)
+{
+	union fu740_spi_reg_csmode csmode;
+	union fu740_spi_reg_fctrl fctrl;
+
+	struct fu740_spi_ctrl *spictrl_reg = fu740_spi_ctrls[slave->bus];
+	struct fu740_spi_config *config = &fu740_spi_configs[slave->bus];
+
+	if ((config->pha > 1)
+		|| (config->pol > 1)
+		|| (config->fmt_config.protocol > 2)
+		|| (config->fmt_config.endianness > 1)
+		|| (config->fmt_config.bits_per_frame > 8))
+		return -1;
+
+	write32(&spictrl_reg->sckdiv, fu740_spi_min_clk_divisor(clock_get_pclk(), config->freq));
+
+	/* disable direct memory-mapped spi flash mode */
+	//TODO test if we need to disable it before changing the settings
+	fctrl.raw_bits = 0;
+	fctrl.en = 0;
+	write32(&spictrl_reg->fctrl.raw_bits, fctrl.raw_bits);
+
+	csmode.raw_bits = 0;
+	csmode.mode = FU740_SPI_CSMODE_HOLD;
+	write32(&spictrl_reg->csmode.raw_bits, csmode.raw_bits);
+	char din[10];
+	char dout[10] = { 0x66 };
+	slave->ctrlr->xfer(slave, dout, 1, din, 0);
+	dout[0] = 0x99;
+	slave->ctrlr->xfer(slave, dout, 1, din, 0);
+	int addr = 0x200;
+	dout[0] = 0x03;
+	dout[1] = (addr >> 16) & 0xFF;
+	dout[2] = (addr >> 8) & 0xFF;
+	dout[3] = addr & 0xFF;
+	slave->ctrlr->xfer(slave, dout, 4, din, 10);
+	csmode.mode = FU740_SPI_CSMODE_AUTO;
+	write32(&spictrl_reg->csmode.raw_bits, csmode.raw_bits);
+	din[9] = 0;
+	return 0;
+}
+
+struct spi_ctrlr fu740_spi_ctrlr = {
+	.xfer  = fu740_spi_xfer,
+	.setup = fu740_spi_setup,
+	.claim_bus = fu740_spi_claim_bus,
+	.release_bus = fu740_spi_release_bus,
+	.max_xfer_size = SPI_CTRLR_DEFAULT_MAX_XFER_SIZE,
+};
+
+const struct spi_ctrlr_buses spi_ctrlr_bus_map[] = {
+	{
+		.bus_start = 0,
+		.bus_end = 2,
+		.ctrlr = &fu740_spi_ctrlr,
+	}
+};
+
+const size_t spi_ctrlr_bus_map_count = ARRAY_SIZE(spi_ctrlr_bus_map);