1 files changed, 393 insertions, 0 deletions
diff --git a/payloads/libpayload/drivers/i8042/i8042.c b/payloads/libpayload/drivers/i8042/i8042.c
new file mode 100644
index 0000000000..1bf18556f2
--- /dev/null
+++ b/payloads/libpayload/drivers/i8042/i8042.c
@@ -0,0 +1,393 @@
+/*
+ * This file is part of the libpayload project.
+ *
+ * Patrick Rudolph 2017 <siro@das-labor.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <libpayload-config.h>
+#include <libpayload.h>
+#include <stddef.h>
+
+/* Overflowing FIFO implementation */
+
+struct fifo {
+	u8 *buf;
+	size_t tx;
+	size_t rx;
+	size_t len;
+};
+
+/** Initialize a new fifo queue.
+ * Initialize a new fifo with length @len.
+ * @len: Length of new fifo
+ * Returns NULL on error.
+ */
+static struct fifo *fifo_init(size_t len)
+{
+	struct fifo *ret;
+
+	ret = malloc(sizeof(*ret));
+	if (!ret)
+		return NULL;
+
+	memset(ret, 0, sizeof(*ret));
+
+	ret->buf = malloc(len);
+	if (!ret->buf) {
+		free(ret);
+		return NULL;
+	}
+
+	ret->len = len;
+
+	return ret;
+}
+
+/** Push object onto fifo queue.
+ * Pushes a new object onto the fifo. In case the fifo
+ * is full the oldest object is overwritten.
+ * @fifo: Fifo to use
+ * @c: Element to push
+ */
+static void fifo_push(struct fifo *fifo, u8 c)
+{
+	fifo->buf[fifo->tx++] = c;
+	fifo->tx = fifo->tx % fifo->len;
+	if (fifo->tx == fifo->rx)
+		fifo->rx++;
+	fifo->rx = fifo->rx % fifo->len;
+}
+
+/** Test fifo queue element count.
+ * Returns 1 if fifo is empty.
+ * @fifo: Fifo to use
+ */
+static int fifo_is_empty(struct fifo *fifo)
+{
+	return fifo->tx == fifo->rx;
+}
+
+/** Pop element from fifo queue.
+ * Returns the oldest object from queue if any.
+ * In case the queue is empty 0 is returned.
+ * @fifo: Fifo to use
+ */
+static u8 fifo_pop(struct fifo *fifo)
+{
+	u8 ret;
+
+	if (fifo_is_empty(fifo))
+		return 0;
+
+	ret = fifo->buf[fifo->rx++];
+	fifo->rx = fifo->rx % fifo->len;
+
+	return ret;
+}
+
+/** Destroys a fifo queue.
+ * @fifo: Fifo to use
+ */
+static void fifo_destroy(struct fifo *fifo)
+{
+	if (fifo && fifo->buf)
+		free(fifo->buf);
+	if (fifo)
+		free(fifo);
+}
+
+/* i8042 keyboard controller implementation */
+
+static inline u8 read_status(void) { return inb(0x64); }
+static inline u8 read_data(void) { return inb(0x60); }
+static inline void write_cmd(u8 cmd) { outb(cmd, 0x64); }
+static inline void write_data(u8 data) { outb(data, 0x60); }
+
+#define OBF 1
+#define IBF 2
+
+/* Keyboard controller methods */
+static int initialized = 0;
+static int kbc_init = 0;
+static struct fifo *aux_fifo = NULL;
+static struct fifo *ps2_fifo = NULL;
+
+static int i8042_cmd_with_response(u8 cmd);
+
+/** Wait for command ready.
+ * Wait for the keyboard controller to accept a new command.
+ * Returns: 0 on timeout
+ */
+static u8 i8042_wait_cmd_rdy(void)
+{
+	int retries = 10000;
+	while (retries-- && (read_status() & IBF))
+		udelay(50);
+
+	return retries > 0;
+}
+
+/** Wait for data ready.
+ * Wait for the keyboard controller to accept new data.
+ * Returns: 0 on timeout
+ */
+static u8 i8042_wait_data_rdy(void)
+{
+	int retries = 10000;
+	while (retries-- && !(read_status() & OBF))
+		udelay(50);
+
+	return retries > 0;
+}
+
+/** Keyboard controller has a ps2 port.
+ * Returns if ps2 port is available.
+ */
+size_t i8042_has_ps2(void)
+{
+	return !!ps2_fifo;
+}
+
+/** Keyboard controller has an aux port.
+ * Returns if aux port is available.
+ */
+size_t i8042_has_aux(void)
+{
+	return !!aux_fifo;
+}
+
+/**
+ * Probe for keyboard controller
+ * Returns: 1 for success, 0 for failure
+ */
+u8 i8042_probe(void)
+{
+	if (initialized)
+		return 1;
+
+	aux_fifo = NULL;
+	ps2_fifo = NULL;
+
+	/* If 0x64 returns 0xff, then we have no keyboard
+	 * controller */
+	if (read_status() == 0xFF)
+		return 0;
+
+	if (!i8042_wait_cmd_rdy())
+		return 0;
+
+	kbc_init = 1;
+
+	/* Disable first device */
+	if (i8042_cmd(0xad) != 0) {
+		kbc_init = 0;
+		return 0;
+	}
+
+	/* Disable second device */
+	if (i8042_cmd(0xa7) != 0) {
+		kbc_init = 0;
+		return 0;
+	}
+
+	/* Flush buffer */
+	while (read_status() & OBF)
+		read_data();
+
+	/* Self test. */
+	if (i8042_cmd_with_response(0xaa) != 0x55) {
+		kbc_init = 0;
+		return 0;
+	}
+
+	/* Test secondary port */
+	if (i8042_cmd_with_response(0xa9) == 0)
+		aux_fifo = fifo_init(4 * 32);
+
+	/* Test first PS/2 port */
+	if (i8042_cmd_with_response(0xab) == 0)
+		ps2_fifo = fifo_init(2 * 16);
+
+	kbc_init = 0;
+
+	initialized = aux_fifo || ps2_fifo;
+
+	return initialized;
+}
+
+/* Close the keyboard controller */
+void i8042_close(void)
+{
+	if (!initialized)
+		return;
+
+	fifo_destroy(aux_fifo);
+	fifo_destroy(ps2_fifo);
+
+	initialized = 0;
+	aux_fifo = NULL;
+	ps2_fifo = NULL;
+}
+
+/** Send command to keyboard controller.
+ * @param cmd: The command to be send.
+ * returns: 0 on success, -1 on failure.
+ */
+int i8042_cmd(u8 cmd)
+{
+	if (!initialized && !kbc_init)
+		return -1;
+
+	if (!i8042_wait_cmd_rdy())
+		return -1;
+
+	write_cmd(cmd);
+
+	if (!i8042_wait_cmd_rdy())
+		return -1;
+
+	return 0;
+}
+
+/** Send command to keyboard controller.
+ * @param cmd: The command to be send.
+ * returns: Response on success, -1 on failure.
+ */
+static int i8042_cmd_with_response(u8 cmd)
+{
+	const int ret = i8042_cmd(cmd);
+	if (ret != 0)
+		return ret;
+
+	if (!i8042_wait_data_rdy())
+		return -1;
+
+	return read_data();
+}
+
+/** Send additional data to keyboard controller.
+ * @param data The data to be send.
+ */
+void i8042_write_data(u8 data)
+{
+	if (!initialized)
+		return;
+
+	if (!i8042_wait_cmd_rdy())
+		return;
+
+	write_data(data);
+
+	if (!i8042_wait_cmd_rdy())
+		return;
+}
+
+/**
+ * Probe for keyboard controller data and queue it.
+ */
+static void i8042_data_poll(void)
+{
+	u8 c;
+
+	if (!initialized)
+		return;
+
+	c = read_status();
+	while ((c != 0xFF) && (c & OBF)) {
+		const u8 in = read_data();
+		/* Assume "second PS/2 port output buffer full" flag works */
+		struct fifo *const fifo = (c & 0x20) ? aux_fifo : ps2_fifo;
+		if (fifo)
+			fifo_push(fifo, in);
+
+		c = read_status();
+	}
+}
+
+/** Keyboard controller data ready status.
+ * Signals that keyboard data is ready for reading.
+ */
+u8 i8042_data_ready_ps2(void)
+{
+	i8042_data_poll();
+	return !fifo_is_empty(ps2_fifo);
+}
+
+/** Keyboard controller data ready status.
+ * Signals that mouse data is ready for reading.
+ */
+u8 i8042_data_ready_aux(void)
+{
+	i8042_data_poll();
+	return !fifo_is_empty(aux_fifo);
+}
+
+/**
+ * Returns available keyboard data, if any.
+ */
+u8 i8042_read_data_ps2(void)
+{
+	i8042_data_poll();
+	return fifo_pop(ps2_fifo);
+}
+
+/**
+ * Returns available mouse data, if any.
+ */
+u8 i8042_read_data_aux(void)
+{
+	i8042_data_poll();
+	return fifo_pop(aux_fifo);
+}
+
+/**
+ * Waits for keyboard data.
+ * Waits for up to 500msec to receive data.
+ * Returns: -1 on timeout, data received otherwise
+ */
+int i8042_wait_read_ps2(void)
+{
+	int retries = 10000;
+
+	while (retries-- && !i8042_data_ready_ps2())
+		udelay(50);
+
+	return (retries <= 0) ? -1 : i8042_read_data_ps2();
+}
+
+/** Waits for mouse data.
+ * Waits for up to 500msec to receive data.
+ * Returns: -1 on timeout, data received otherwise
+ */
+int i8042_wait_read_aux(void)
+{
+	int retries = 10000;
+
+	while (retries-- && !i8042_data_ready_aux())
+		udelay(50);
+
+	return (retries <= 0) ? -1 : i8042_read_data_aux();
+}