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-rw-r--r--src/drivers/spi/Makefile.inc6
-rw-r--r--src/drivers/spi/bitbang.c84
-rw-r--r--src/include/spi_bitbang.h32
-rw-r--r--src/soc/rockchip/rk3399/spi_bitbang.c157
4 files changed, 279 insertions, 0 deletions
diff --git a/src/drivers/spi/Makefile.inc b/src/drivers/spi/Makefile.inc
index 3f68541448..edea392db1 100644
--- a/src/drivers/spi/Makefile.inc
+++ b/src/drivers/spi/Makefile.inc
@@ -18,6 +18,7 @@ smm-$(CONFIG_DEBUG_SMI) += flashconsole.c
endif
bootblock-y += spi-generic.c
+bootblock-y += bitbang.c
bootblock-$(CONFIG_COMMON_CBFS_SPI_WRAPPER) += cbfs_spi.c
bootblock-$(CONFIG_SPI_FLASH) += spi_flash.c
bootblock-$(CONFIG_BOOT_DEVICE_SPI_FLASH_RW_NOMMAP_EARLY) += boot_device_rw_nommap.c
@@ -34,6 +35,7 @@ bootblock-$(CONFIG_SPI_FLASH_WINBOND) += winbond.c
bootblock-$(CONFIG_SPI_FRAM_RAMTRON) += ramtron.c
romstage-y += spi-generic.c
+romstage-y += bitbang.c
romstage-$(CONFIG_COMMON_CBFS_SPI_WRAPPER) += cbfs_spi.c
romstage-$(CONFIG_SPI_FLASH) += spi_flash.c
romstage-$(CONFIG_BOOT_DEVICE_SPI_FLASH_RW_NOMMAP_EARLY) += boot_device_rw_nommap.c
@@ -50,6 +52,7 @@ romstage-$(CONFIG_SPI_FLASH_WINBOND) += winbond.c
romstage-$(CONFIG_SPI_FRAM_RAMTRON) += ramtron.c
verstage-y += spi-generic.c
+verstage-y += bitbang.c
verstage-$(CONFIG_COMMON_CBFS_SPI_WRAPPER) += cbfs_spi.c
verstage-$(CONFIG_SPI_FLASH) += spi_flash.c
verstage-$(CONFIG_BOOT_DEVICE_SPI_FLASH_RW_NOMMAP_EARLY) += boot_device_rw_nommap.c
@@ -66,6 +69,7 @@ verstage-$(CONFIG_SPI_FLASH_WINBOND) += winbond.c
verstage-$(CONFIG_SPI_FRAM_RAMTRON) += ramtron.c
ramstage-y += spi-generic.c
+ramstage-y += bitbang.c
ramstage-$(CONFIG_COMMON_CBFS_SPI_WRAPPER) += cbfs_spi.c
ramstage-$(CONFIG_SPI_FLASH) += spi_flash.c
ramstage-$(CONFIG_BOOT_DEVICE_SPI_FLASH_RW_NOMMAP) += boot_device_rw_nommap.c
@@ -83,6 +87,7 @@ ramstage-$(CONFIG_SPI_FRAM_RAMTRON) += ramtron.c
ifeq ($(CONFIG_SPI_FLASH_SMM),y)
smm-y += spi-generic.c
+smm-y += bitbang.c
# SPI flash driver interface
smm-$(CONFIG_SPI_FLASH) += spi_flash.c
smm-$(CONFIG_BOOT_DEVICE_SPI_FLASH_RW_NOMMAP) += boot_device_rw_nommap.c
@@ -102,5 +107,6 @@ smm-$(CONFIG_SPI_FRAM_RAMTRON) += ramtron.c
endif
postcar-y += spi-generic.c
+postcar-y += bitbang.c
postcar-$(CONFIG_BOOT_DEVICE_SPI_FLASH_RW_NOMMAP_EARLY) += boot_device_rw_nommap.c
postcar-$(CONFIG_SPI_FLASH) += spi_flash.c
diff --git a/src/drivers/spi/bitbang.c b/src/drivers/spi/bitbang.c
new file mode 100644
index 0000000000..d858345859
--- /dev/null
+++ b/src/drivers/spi/bitbang.c
@@ -0,0 +1,84 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright 2018 Google LLC
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <console/console.h>
+#include <delay.h>
+#include <spi_bitbang.h>
+
+/* Set to 1 to dump all SPI transfers to the UART. */
+#define TRACE 0
+/*
+ * In theory, this should work fine with 0 delay since the bus is fully clocked
+ * by the master and the slave just needs to follow clock transitions whenever
+ * they happen. We're not going to be "too fast" by bit-banging anyway. However,
+ * if something doesn't work right, try increasing this value to slow it down.
+ */
+#define HALF_CLOCK_US 0
+
+int spi_bitbang_claim_bus(const struct spi_bitbang_ops *ops)
+{
+ ops->set_cs(ops, 0);
+ return 0;
+}
+
+void spi_bitbang_release_bus(const struct spi_bitbang_ops *ops)
+{
+ ops->set_cs(ops, 1);
+}
+
+/* Implements a CPOL=0, CPH=0, MSB first 8-bit controller. */
+int spi_bitbang_xfer(const struct spi_bitbang_ops *ops, const void *dout,
+ size_t bytes_out, void *din, size_t bytes_in)
+{
+ if (TRACE) {
+ if (bytes_in && bytes_out)
+ printk(BIOS_SPEW, "!");
+ else if (bytes_in)
+ printk(BIOS_SPEW, "<");
+ else if (bytes_out)
+ printk(BIOS_SPEW, ">");
+ }
+
+ while (bytes_out || bytes_in) {
+ int i;
+ uint8_t in_byte = 0, out_byte = 0;
+ if (bytes_out) {
+ out_byte = *(const uint8_t *)dout++;
+ bytes_out--;
+ if (TRACE)
+ printk(BIOS_SPEW, "%02x", out_byte);
+ }
+ for (i = 7; i >= 0; i--) {
+ ops->set_mosi(ops, !!(out_byte & (1 << i)));
+ if (HALF_CLOCK_US)
+ udelay(HALF_CLOCK_US);
+ ops->set_clk(ops, 1);
+ in_byte |= !!ops->get_miso(ops) << i;
+ if (HALF_CLOCK_US)
+ udelay(HALF_CLOCK_US);
+ ops->set_clk(ops, 0);
+ }
+ if (bytes_in) {
+ *(uint8_t *)din++ = in_byte;
+ bytes_in--;
+ if (TRACE)
+ printk(BIOS_SPEW, "%02x", in_byte);
+ }
+ }
+
+ if (TRACE)
+ printk(BIOS_SPEW, "\n");
+ return 0;
+}
diff --git a/src/include/spi_bitbang.h b/src/include/spi_bitbang.h
new file mode 100644
index 0000000000..710fefb1bf
--- /dev/null
+++ b/src/include/spi_bitbang.h
@@ -0,0 +1,32 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright 2018 Google LLC
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+#ifndef _SPI_BITBANG_H_
+#define _SPI_BITBANG_H_
+
+#include <types.h>
+
+struct spi_bitbang_ops {
+ int (*get_miso)(const struct spi_bitbang_ops *ops);
+ void (*set_mosi)(const struct spi_bitbang_ops *ops, int value);
+ void (*set_clk)(const struct spi_bitbang_ops *ops, int value);
+ void (*set_cs)(const struct spi_bitbang_ops *ops, int value);
+};
+
+int spi_bitbang_claim_bus(const struct spi_bitbang_ops *ops);
+void spi_bitbang_release_bus(const struct spi_bitbang_ops *ops);
+int spi_bitbang_xfer(const struct spi_bitbang_ops *ops, const void *dout,
+ size_t bytes_out, void *din, size_t bytes_in);
+
+#endif /* _SPI_BITBANG_H_ */
diff --git a/src/soc/rockchip/rk3399/spi_bitbang.c b/src/soc/rockchip/rk3399/spi_bitbang.c
new file mode 100644
index 0000000000..628cc16764
--- /dev/null
+++ b/src/soc/rockchip/rk3399/spi_bitbang.c
@@ -0,0 +1,157 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright 2018 Google LLC
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+/* Compile this driver in place of common/spi.c for bitbang testing.
+ NOTE: Also need to adjust board-specific code for GPIO pinmux! */
+
+#include <assert.h>
+#include <gpio.h>
+#include <soc/spi.h>
+#include <spi_bitbang.h>
+#include <spi_flash.h>
+
+struct rockchip_bitbang_slave {
+ struct spi_bitbang_ops ops;
+ gpio_t miso;
+ gpio_t mosi;
+ gpio_t clk;
+ gpio_t cs;
+};
+
+static int get_miso(const struct spi_bitbang_ops *ops)
+{
+ const struct rockchip_bitbang_slave *slave =
+ container_of(ops, const struct rockchip_bitbang_slave, ops);
+ return gpio_get(slave->miso);
+}
+
+static void set_mosi(const struct spi_bitbang_ops *ops, int value)
+{
+ const struct rockchip_bitbang_slave *slave =
+ container_of(ops, const struct rockchip_bitbang_slave, ops);
+ gpio_set(slave->mosi, value);
+}
+
+static void set_clk(const struct spi_bitbang_ops *ops, int value)
+{
+ const struct rockchip_bitbang_slave *slave =
+ container_of(ops, const struct rockchip_bitbang_slave, ops);
+ gpio_set(slave->clk, value);
+}
+
+static void set_cs(const struct spi_bitbang_ops *ops, int value)
+{
+ const struct rockchip_bitbang_slave *slave =
+ container_of(ops, const struct rockchip_bitbang_slave, ops);
+ gpio_set(slave->cs, value);
+}
+
+/* Can't use GPIO() here because of bug in GCC version used by Chromium OS. */
+static const struct rockchip_bitbang_slave slaves[] = {
+ [0] = {
+ .ops = { get_miso, set_mosi, set_clk, set_cs },
+ .miso = { .port = 3, .bank = GPIO_A, .idx = 4 },
+ .mosi = { .port = 3, .bank = GPIO_A, .idx = 5 },
+ .clk = { .port = 3, .bank = GPIO_A, .idx = 6 },
+ .cs = { .port = 3, .bank = GPIO_A, .idx = 7 },
+ },
+ [1] = {
+ .ops = { get_miso, set_mosi, set_clk, set_cs },
+ .miso = { .port = 1, .bank = GPIO_A, .idx = 7 },
+ .mosi = { .port = 1, .bank = GPIO_B, .idx = 0 },
+ .clk = { .port = 1, .bank = GPIO_B, .idx = 1 },
+ .cs = { .port = 1, .bank = GPIO_B, .idx = 2 },
+ },
+ [2] = {
+ .ops = { get_miso, set_mosi, set_clk, set_cs },
+ .miso = { .port = 2, .bank = GPIO_B, .idx = 1 },
+ .mosi = { .port = 2, .bank = GPIO_B, .idx = 2 },
+ .clk = { .port = 2, .bank = GPIO_B, .idx = 3 },
+ .cs = { .port = 2, .bank = GPIO_B, .idx = 4 },
+ },
+ [3] = {
+ .ops = { get_miso, set_mosi, set_clk, set_cs },
+ .miso = { .port = 1, .bank = GPIO_B, .idx = 7 },
+ .mosi = { .port = 1, .bank = GPIO_C, .idx = 0 },
+ .clk = { .port = 1, .bank = GPIO_C, .idx = 1 },
+ .cs = { .port = 1, .bank = GPIO_C, .idx = 2 },
+ },
+ [4] = {
+ .ops = { get_miso, set_mosi, set_clk, set_cs },
+ .miso = { .port = 3, .bank = GPIO_A, .idx = 0 },
+ .mosi = { .port = 3, .bank = GPIO_A, .idx = 1 },
+ .clk = { .port = 3, .bank = GPIO_A, .idx = 2 },
+ .cs = { .port = 3, .bank = GPIO_A, .idx = 3 },
+ },
+ [5] = {
+ .ops = { get_miso, set_mosi, set_clk, set_cs },
+ .miso = { .port = 2, .bank = GPIO_C, .idx = 4 },
+ .mosi = { .port = 2, .bank = GPIO_C, .idx = 5 },
+ .clk = { .port = 2, .bank = GPIO_C, .idx = 6 },
+ .cs = { .port = 2, .bank = GPIO_C, .idx = 7 },
+ },
+};
+
+void rockchip_spi_init(unsigned int bus, unsigned int ignored_speed_hz)
+{
+ assert(bus >= 0 && bus < ARRAY_SIZE(slaves));
+
+ gpio_output(slaves[bus].cs, 1);
+ gpio_output(slaves[bus].clk, 0);
+ gpio_input(slaves[bus].miso);
+ gpio_output(slaves[bus].mosi, 0);
+}
+
+void rockchip_spi_set_sample_delay(unsigned int bus, unsigned int delay_ns)
+{
+ /* not supported, and not necessary for slow bitbang speeds */
+}
+
+static int spi_ctrlr_claim_bus(const struct spi_slave *slave)
+{
+ assert(slave->bus >= 0 && slave->bus < ARRAY_SIZE(slaves));
+ return spi_bitbang_claim_bus(&slaves[slave->bus].ops);
+}
+
+static void spi_ctrlr_release_bus(const struct spi_slave *slave)
+{
+ assert(slave->bus >= 0 && slave->bus < ARRAY_SIZE(slaves));
+ spi_bitbang_release_bus(&slaves[slave->bus].ops);
+}
+
+static int spi_ctrlr_xfer(const struct spi_slave *slave, const void *dout,
+ size_t bytes_out, void *din, size_t bytes_in)
+{
+ assert(slave->bus >= 0 && slave->bus < ARRAY_SIZE(slaves));
+ return spi_bitbang_xfer(&slaves[slave->bus].ops,
+ dout, bytes_out, din, bytes_in);
+}
+
+static const struct spi_ctrlr spi_ctrlr = {
+ .claim_bus = spi_ctrlr_claim_bus,
+ .release_bus = spi_ctrlr_release_bus,
+ .xfer = spi_ctrlr_xfer,
+ .max_xfer_size = 65535,
+};
+
+const struct spi_ctrlr_buses spi_ctrlr_bus_map[] = {
+ {
+ .ctrlr = &spi_ctrlr,
+ .bus_start = 0,
+ .bus_end = ARRAY_SIZE(slaves) - 1,
+ },
+};
+
+const size_t spi_ctrlr_bus_map_count = ARRAY_SIZE(spi_ctrlr_bus_map);