Cr50: Remove CONFIG_HOSTCMD_SPS support

This config option allowed us to disable the TPM protocol on the
SPI slave bus and replace it with our EC-style host command
protocol. We only used this for early testing and don't need it
anymore, so we can get rid of it completely for this SoC.

BUG=none
BRANCH=none
TEST=make buildall; test on cr50

Change-Id: I2126537e8bcc78e583cf426a3a83962c9ff1a121
Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/334762
Reviewed-by: Scott Collyer <scollyer@chromium.org>

3 files changed, 1 insertions, 311 deletions

diff --git a/board/cr50/board.h b/board/cr50/board.h
index 730d39dd6a..90635323ae 100644
--- a/board/cr50/board.h
+++ b/board/cr50/board.h
@@ -6,7 +6,7 @@
 #ifndef __CROS_EC_BOARD_H
 #define __CROS_EC_BOARD_H
 
-/* Features that we don't want just yet */
+/* Features that we don't want */
 #undef CONFIG_CMD_LID_ANGLE
 #undef CONFIG_CMD_POWERINDEBUG
 #undef CONFIG_DMA_DEFAULT_HANDLERS
@@ -31,7 +31,6 @@
 
 /* Enable SPI Slave (SPS) module */
 #define CONFIG_SPS
-#define CONFIG_HOSTCMD_SPS
 #define CONFIG_TPM_SPS
 
 /* We don't need to send events to the AP */
diff --git a/chip/g/build.mk b/chip/g/build.mk
index d615a927ed..0d8ae631b2 100644
--- a/chip/g/build.mk
+++ b/chip/g/build.mk
@@ -40,7 +40,6 @@ chip-$(CONFIG_SPI_MASTER)+=spi_master.o
 chip-y+= pmu.o
 chip-y+= trng.o
 chip-$(CONFIG_SPS)+= sps.o
-chip-$(CONFIG_HOSTCMD_SPS)+=sps_hc.o
 chip-$(CONFIG_TPM_SPS)+=sps_tpm.o
 chip-$(CONFIG_WATCHDOG)+=watchdog.o
 
diff --git a/chip/g/sps_hc.c b/chip/g/sps_hc.c
deleted file mode 100644
index 1fe9c6f62a..0000000000
--- a/chip/g/sps_hc.c
+++ /dev/null
@@ -1,308 +0,0 @@
-/* Copyright 2015 The Chromium OS Authors. All rights reserved.
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-
-#include "common.h"
-#include "console.h"
-#include "hooks.h"
-#include "host_command.h"
-#include "sps.h"
-#include "util.h"
-
-/*
- * This implements EC host commands over the SPI bus, using the Cr50 SPS (SPI
- * slave) controller.
- *
- * Host commands are communicated using software flow-control, because most of
- * the embedded controllers either aren't fast enough or don't have any support
- * for hardware flow-control.
- *
- * Every SPI transaction is bi-directional, so when the AP sends commands to
- * the EC, a default "dummy" byte is returned at the same time. The EC
- * preconfigures that default response byte to indicate its status (ready,
- * busy, waiting for more input, etc). Once the AP has sent a complete command
- * message, it continues clocking bytes to the EC (which the EC ignores) and
- * just looks at the response byte that comes back. Once the EC has parsed the
- * command and is ready to reply, it sends a "start of frame" byte, followed by
- * the actual response. The AP continues to read and ignore bytes from the EC
- * until it sees the start of frame byte, and then it knows that the EC's
- * response is starting with the next byte. Refer to include/ec_commands.h for
- * more details.
- */
-
-/* Console output macros */
-#define CPUTS(outstr) cputs(CC_HOSTCMD, outstr)
-#define CPRINTS(format, args...) cprints(CC_HOSTCMD, format, ## args)
-#define CPRINTF(format, args...) cprintf(CC_HOSTCMD, format, ## args)
-
-/*
- * Incoming messages are collected here until they're ready to process. The
- * buffer will start with a struct ec_host_request, followed by whatever data
- * is sent by the master.
- */
-#define RXBUF_MAX 512				/* chosen arbitrarily */
-static uint8_t rxbuf[RXBUF_MAX];
-static unsigned int rxbuf_count;		/* num bytes received */
-static unsigned int rxbuf_needed;		/* num bytes we'd like */
-
-/*
- * Outgoing messages are shoved in here. We need a preamble byte to mark the
- * start of the data stream before the data itself.
- */
-#define TXBUF_MAX 512				/* chosen arbitrarily */
-static uint8_t txbuf[1 + TXBUF_MAX];
-
-static enum spi_state {
-	/* SPI not enabled (initial state, and when chipset is off) */
-	SPI_STATE_DISABLED = 0,
-
-	/* Ready to receive next request */
-	SPI_STATE_READY_TO_RX,
-
-	/* Receiving request */
-	SPI_STATE_RECEIVING_HEADER,
-	SPI_STATE_RECEIVING_BODY,
-
-	/* Processing request */
-	SPI_STATE_PROCESSING,
-
-	/* Sending response */
-	SPI_STATE_SENDING,
-
-	/*
-	 * Received bad data - transaction started before we were ready, or
-	 * packet header from the master didn't parse properly. Ignoring
-	 * received data.
-	 */
-	SPI_STATE_RX_BAD,
-} state;
-
-/* If the chip select is disabled, don't transmit response */
-static int discard_response;
-
-/* Callback to send our response to the master */
-static void cb_send_response_packet(struct host_packet *pkt)
-{
-	uint8_t *bufptr;
-	size_t data_size = pkt->response_size;
-
-	/* Chip Select was deasserted before we got here */
-	if (discard_response) {
-		discard_response = 0;
-		state = SPI_STATE_READY_TO_RX;
-		sps_tx_status(EC_SPI_RX_READY);
-		return;
-	}
-
-	/*
-	 * The pkt->response will start at txbuf[1], which means that
-	 * pkt->response_size doesn't include the preamble byte. We need to
-	 * initialize it and start sending from there.
-	 */
-	txbuf[0] = EC_SPI_FRAME_START;
-	data_size++;
-	bufptr = txbuf;
-	state = SPI_STATE_SENDING;
-
-	/* There's probably still a race condition somewhere... */
-	while (data_size && state == SPI_STATE_SENDING) {
-		size_t cnt = sps_transmit(bufptr, data_size);
-		data_size -= cnt;
-		bufptr += cnt;
-	}
-
-	/* Clock out the end-of-packet marker when we're done. */
-	sps_tx_status(EC_SPI_PAST_END);
-}
-
-static int req_header_looks_good(const struct ec_host_request *req)
-{
-	return (req->struct_version == EC_HOST_REQUEST_VERSION) &&
-		(req->reserved == 0) &&
-		(sizeof(*req) + req->data_len <= RXBUF_MAX);
-}
-
-/* RX FIFO handler (runs in interrupt context) */
-static void hc_rx_handler(uint8_t *data, size_t data_size, int cs_disabled)
-{
-	struct ec_host_request *req = (struct ec_host_request *)rxbuf;
-	static struct host_packet rx_packet;
-	size_t i;
-
-	if (cs_disabled) {
-		if (state == SPI_STATE_PROCESSING) {
-			/*
-			 * A task is preparing a response, but the master has
-			 * stopped caring. Set a flag so when the response is
-			 * ready we'll just throw it away and reset everything.
-			 */
-			discard_response = 1;
-			return;
-		}
-
-		/* Otherwise, just go back to waiting for new input */
-		state = SPI_STATE_READY_TO_RX;
-		sps_tx_status(EC_SPI_RX_READY);
-		return;
-	}
-
-	/* No data == nothing to do */
-	if (!data_size)
-		return;
-
-	switch (state) {
-	case SPI_STATE_READY_TO_RX:
-		/* Starting a new RX transaction. */
-		rxbuf_count = 0;
-		state = SPI_STATE_RECEIVING_HEADER;
-		sps_tx_status(EC_SPI_RECEIVING);
-		/* Need a header first (proto v3 only) */
-		rxbuf_needed = sizeof(*req);
-		break;
-
-	case SPI_STATE_RECEIVING_HEADER:
-	case SPI_STATE_RECEIVING_BODY:
-		/* still gathering bytes */
-		break;
-
-	case SPI_STATE_DISABLED:
-		/*
-		 * The master started a transaction but we weren't ready for it.
-		 * Tell it we weren't ready, and ignore the incoming data until
-		 * the master gives up.
-		 */
-		CPRINTS("SPI not ready (in state %d)", state);
-		sps_tx_status(EC_SPI_NOT_READY);
-		state = SPI_STATE_RX_BAD;
-		return;
-
-	default:
-		/* Anything else doesn't need us to look at the input */
-		return;
-	}
-
-	/* Collect incoming bytes */
-	if (rxbuf_count + data_size > RXBUF_MAX)
-		goto spi_event_error;
-	memcpy(rxbuf + rxbuf_count, data, data_size);
-	rxbuf_count += data_size;
-
-	/* Wait until we have enough */
-	if (rxbuf_count < rxbuf_needed)
-		return;
-
-	switch (state) {
-	case SPI_STATE_RECEIVING_HEADER:
-		/* Got the header - is it okay? */
-		if (!req_header_looks_good(req))
-			goto spi_event_error;
-
-		/* Yep, now need the body */
-		state = SPI_STATE_RECEIVING_BODY;
-		rxbuf_needed += req->data_len;
-
-		/* Still need more bytes? */
-		if (rxbuf_count < rxbuf_needed)
-			return;
-
-		/* FALLTHROUGH */
-
-	case SPI_STATE_RECEIVING_BODY:
-		/* We have all the data we need. */
-		state = SPI_STATE_PROCESSING;
-		sps_tx_status(EC_SPI_PROCESSING);
-
-		/* Hand it off to the host command task for processing */
-		rx_packet.send_response = cb_send_response_packet;
-		rx_packet.request = rxbuf;
-		rx_packet.request_temp = NULL;
-		rx_packet.request_max = RXBUF_MAX;
-		rx_packet.request_size = rxbuf_count;
-		rx_packet.response = txbuf + 1;	/* skip preamble byte */
-		rx_packet.response_max = TXBUF_MAX;
-		rx_packet.response_size = 0;
-		rx_packet.driver_result = EC_RES_SUCCESS;
-		host_packet_receive(&rx_packet);
-		break;
-
-	default:
-		/* shouldn't get here */
-		goto spi_event_error;
-	}
-
-	return;
-
- spi_event_error:
-	/* Error, timeout, or protocol we can't handle.  Ignore data. */
-	sps_tx_status(EC_SPI_RX_BAD_DATA);
-	state = SPI_STATE_RX_BAD;
-
-	CPRINTS("SPI RX BAD DATA");
-	CPRINTF("[rxbuf (%d): ", rxbuf_count);
-	for (i = 0; i < rxbuf_count; i++)
-		CPRINTF("%02x ", rxbuf[i]);
-	CPRINTF("]\n");
-}
-
-static void sps_hc_enable(void)
-{
-	/* I'm not listening, la la la la la ... */
-	sps_tx_status(EC_SPI_NOT_READY);
-
-	/* We are no longer actively processing a transaction */
-	state = SPI_STATE_DISABLED;
-
-	/* Ready to receive */
-	sps_register_rx_handler(SPS_GENERIC_MODE, hc_rx_handler, 0);
-
-	/* Here we go */
-	discard_response = 0;
-	state = SPI_STATE_READY_TO_RX;
-	sps_tx_status(EC_SPI_RX_READY);
-}
-
-static void sps_hc_disable(void)
-{
-	sps_unregister_rx_handler();
-
-	/* We are no longer actively processing a transaction */
-	state = SPI_STATE_DISABLED;
-}
-
-static int sps_get_protocol_info(struct host_cmd_handler_args *args)
-{
-	struct ec_response_get_protocol_info *r = args->response;
-
-	r->protocol_versions = (1 << 3);
-	r->max_request_packet_size = RXBUF_MAX;
-	r->max_response_packet_size = TXBUF_MAX;
-	r->flags = 0;
-
-	args->response_size = sizeof(*r);
-	return EC_SUCCESS;
-}
-DECLARE_HOST_COMMAND(EC_CMD_GET_PROTOCOL_INFO,
-		     sps_get_protocol_info,
-		     EC_VER_MASK(0));
-
-static int command_sps(int argc, char **argv)
-{
-	if (argc > 1) {
-		if (0 != strcasecmp(argv[1], "off"))
-			return EC_ERROR_PARAM1;
-
-		sps_hc_disable();
-		ccprintf("SPS host commands disabled\n");
-		return EC_SUCCESS;
-	}
-
-	sps_hc_enable();
-	ccprintf("SPS host commands enabled\n");
-	return EC_SUCCESS;
-}
-
-DECLARE_CONSOLE_COMMAND(spshc, command_sps,
-			"[off]",
-			"Enable (default) or disable SPS host commands",
-			NULL);