--- /dev/null
+/*
+ * Copyright © 2013 Keith Packard <keithp@keithp.com>
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ */
+
+#include "ao.h"
+#include "ao_sdcard.h"
+
+#define ao_sdcard_get_slow() ao_spi_get(AO_SDCARD_SPI_BUS, AO_SPI_SPEED_250kHz)
+#define ao_sdcard_get() ao_spi_get(AO_SDCARD_SPI_BUS, AO_SPI_SPEED_FAST)
+#define ao_sdcard_put() ao_spi_put(AO_SDCARD_SPI_BUS)
+#define ao_sdcard_send_fixed(d,l) ao_spi_send_fixed((d), (l), AO_SDCARD_SPI_BUS)
+#define ao_sdcard_send(d,l) ao_spi_send((d), (l), AO_SDCARD_SPI_BUS)
+#define ao_sdcard_recv(d,l) ao_spi_recv((d), (l), AO_SDCARD_SPI_BUS)
+#define ao_sdcard_select() ao_gpio_set(AO_SDCARD_SPI_CS_PORT,AO_SDCARD_SPI_CS_PIN,AO_SDCARD_SPI_CS,0)
+#define ao_sdcard_deselect() ao_gpio_set(AO_SDCARD_SPI_CS_PORT,AO_SDCARD_SPI_CS_PIN,AO_SDCARD_SPI_CS,1)
+
+
+static uint8_t initialized;
+static uint8_t present;
+static uint8_t mutex;
+static enum ao_sdtype sdtype;
+
+#define ao_sdcard_lock() ao_mutex_get(&mutex)
+#define ao_sdcard_unlock() ao_mutex_put(&mutex)
+
+#if 0
+#define DBG(...) printf(__VA_ARGS__)
+#else
+#define DBG(...)
+#endif
+
+/*
+ * Send an SD command and await the status reply
+ */
+
+static uint8_t
+ao_sdcard_send_cmd(uint8_t cmd, uint32_t arg)
+{
+ uint8_t data[6];
+ uint8_t reply;
+ int i;
+
+ DBG ("\tsend_cmd %d arg %08x\n", cmd, arg);
+ if (cmd != SDCARD_GO_IDLE_STATE) {
+ for (i = 0; i < SDCARD_CMD_TIMEOUT; i++) {
+ ao_sdcard_recv(&reply, 1);
+ if (reply == 0xff)
+ break;
+ }
+ if (i == SDCARD_CMD_TIMEOUT)
+ return SDCARD_STATUS_TIMEOUT;
+ }
+
+ data[0] = cmd & 0x3f | 0x40;
+ data[1] = arg >> 24;
+ data[2] = arg >> 16;
+ data[3] = arg >> 8;
+ data[4] = arg;
+ if (cmd == SDCARD_GO_IDLE_STATE)
+ data[5] = 0x95; /* Valid for 0 arg */
+ else if (cmd == SDCARD_SEND_IF_COND)
+ data[5] = 0x87; /* Valid for 0x1aa arg */
+ else
+ data[5] = 0xff; /* no CRC */
+ ao_sdcard_send(data, 6);
+
+ /* The first reply byte will be the status,
+ * which must have the high bit clear
+ */
+ for (i = 0; i < SDCARD_CMD_TIMEOUT; i++) {
+ ao_sdcard_recv(&reply, 1);
+ DBG ("\t\tgot byte %02x\n", reply);
+ if ((reply & 0x80) == 0)
+ return reply;
+ }
+ return SDCARD_STATUS_TIMEOUT;
+}
+
+/*
+ * Retrieve any reply, discarding the trailing CRC byte
+ */
+static void
+ao_sdcard_recv_reply(uint8_t *reply, int len)
+{
+ uint8_t discard;
+
+ if (len)
+ ao_sdcard_recv(reply, len);
+ /* trailing byte */
+ ao_sdcard_recv(&discard, 1);
+}
+
+/*
+ * Wait while the card is busy. The
+ * card will return a stream of 0xff
+ * until it isn't busy anymore
+ */
+static void
+ao_sdcard_wait_busy(void)
+{
+ uint8_t v;
+
+ do {
+ ao_sdcard_recv(&v, 1);
+ } while (v != 0xff);
+ ao_sdcard_send_fixed(0xff, 1);
+}
+
+static uint8_t
+ao_sdcard_go_idle_state(void)
+{
+ uint8_t ret;
+
+ DBG ("go_idle_state\n");
+ ao_sdcard_select();
+ ret = ao_sdcard_send_cmd(SDCARD_GO_IDLE_STATE, 0);
+ ao_sdcard_recv_reply(NULL, 0);
+ ao_sdcard_deselect();
+ DBG ("\tgo_idle_state status %02x\n", ret);
+ return ret;
+}
+
+static uint8_t
+ao_sdcard_send_op_cond(void)
+{
+ uint8_t ret;
+
+ DBG ("send_op_cond\n");
+ ao_sdcard_select();
+ ret = ao_sdcard_send_cmd(SDCARD_SEND_OP_COND, 0);
+ ao_sdcard_recv_reply(NULL, 0);
+ ao_sdcard_deselect();
+ DBG ("\tsend_op_cond %02x\n", ret);
+ return ret;
+}
+
+static uint8_t
+ao_sdcard_send_if_cond(uint32_t arg, uint8_t send_if_cond_response[4])
+{
+ uint8_t ret;
+
+ DBG ("send_if_cond\n");
+ ao_sdcard_select();
+ ret = ao_sdcard_send_cmd(SDCARD_SEND_IF_COND, arg);
+ if (ret != SDCARD_STATUS_IDLE_STATE) {
+ DBG ("\tsend_if_cond failed %02x\n", ret);
+ return ret;
+ }
+ ao_sdcard_recv_reply(send_if_cond_response, 4);
+ DBG ("send_if_cond status %02x response %02x %02x %02x %02x\n",
+ ret,
+ send_if_cond_response[0],
+ send_if_cond_response[1],
+ send_if_cond_response[2],
+ send_if_cond_response[3]);
+ ao_sdcard_deselect();
+ return ret;
+}
+
+static uint8_t
+ao_sdcard_set_blocklen(uint32_t blocklen)
+{
+ uint8_t ret;
+
+ DBG ("set_blocklen %d\n", blocklen);
+ ao_sdcard_select();
+ ret = ao_sdcard_send_cmd(SDCARD_SET_BLOCKLEN, blocklen);
+ ao_sdcard_recv_reply(NULL, 0);
+ if (ret != SDCARD_STATUS_READY_STATE)
+ DBG ("\tsend_if_cond failed %02x\n", ret);
+ return ret;
+
+}
+
+static uint8_t
+ao_sdcard_app_cmd(void)
+{
+ uint8_t ret;
+
+ DBG ("app_cmd\n");
+ ao_sdcard_select();
+ ret = ao_sdcard_send_cmd(SDCARD_APP_CMD, 0);
+ ao_sdcard_recv_reply(NULL, 0);
+ ao_sdcard_deselect();
+ DBG ("\tapp_cmd status %02x\n");
+ return ret;
+}
+
+static uint8_t
+ao_sdcard_app_send_op_cond(uint32_t arg)
+{
+ uint8_t ret;
+
+ ret = ao_sdcard_app_cmd();
+ if (ret != SDCARD_STATUS_IDLE_STATE)
+ return ret;
+ DBG("send_op_comd\n");
+ ao_sdcard_select();
+ ret = ao_sdcard_send_cmd(SDCARD_APP_SEND_OP_COMD, arg);
+ ao_sdcard_recv_reply(NULL, 0);
+ ao_sdcard_deselect();
+ DBG ("\tapp_send_op_cond status %02x\n", ret);
+ return ret;
+}
+
+static uint8_t
+ao_sdcard_read_ocr(uint8_t read_ocr_response[4])
+{
+ uint8_t ret;
+
+ DBG ("read_ocr\n");
+ ao_sdcard_select();
+ ret = ao_sdcard_send_cmd(SDCARD_READ_OCR, 0);
+ if (ret != SDCARD_STATUS_READY_STATE)
+ DBG ("\tread_ocr failed %02x\n", ret);
+ else {
+ ao_sdcard_recv_reply(read_ocr_response, 4);
+ DBG ("\tread_ocr status %02x response %02x %02x %02x %02x\n", ret,
+ read_ocr_response[0], read_ocr_response[1],
+ read_ocr_response[2], read_ocr_response[3]);
+ }
+ ao_sdcard_deselect();
+ return ret;
+}
+
+static void
+ao_sdcard_setup(void)
+{
+ int i;
+ uint8_t ret;
+ uint8_t response[10];
+
+ DBG ("Testing sdcard\n");
+
+ ao_sdcard_get_slow();
+ /*
+ * min 74 clocks with CS high
+ */
+ ao_sdcard_send_fixed(0xff, 10);
+
+ ao_delay(AO_MS_TO_TICKS(10));
+
+ /* Reset the card and get it into SPI mode */
+
+ for (i = 0; i < SDCARD_IDLE_WAIT; i++) {
+ if (ao_sdcard_go_idle_state() == SDCARD_STATUS_IDLE_STATE)
+ break;
+ }
+ if (i == SDCARD_IDLE_WAIT)
+ goto bail;
+
+ /* Figure out what kind of card we have */
+
+ sdtype = ao_sdtype_unknown;
+
+ if (ao_sdcard_send_if_cond(0x1aa, response) == SDCARD_STATUS_IDLE_STATE) {
+ uint32_t arg = 0;
+ uint8_t sdver2 = 0;
+
+ /* Check for SD version 2 */
+ if ((response[2] & 0xf) == 1 && response[3] == 0xaa) {
+ arg = 0x40000000;
+ sdver2 = 1;
+ }
+
+ for (i = 0; i < SDCARD_IDLE_WAIT; i++) {
+ ret = ao_sdcard_app_send_op_cond(arg);
+ if (ret != SDCARD_STATUS_IDLE_STATE)
+ break;
+ }
+ if (ret != SDCARD_STATUS_READY_STATE) {
+ /* MMC */
+ for (i = 0; i < SDCARD_IDLE_WAIT; i++) {
+ ret = ao_sdcard_send_op_cond();
+ if (ret != SDCARD_STATUS_IDLE_STATE)
+ break;
+ }
+ if (ret != SDCARD_STATUS_READY_STATE)
+ goto bail;
+ sdtype = ao_sdtype_mmc3;
+ } else {
+ /* SD */
+ if (sdver2 != 0) {
+ ret = ao_sdcard_read_ocr(response);
+ if (ret != SDCARD_STATUS_READY_STATE)
+ goto bail;
+ if ((response[0] & 0xc0) == 0xc0)
+ sdtype = ao_sdtype_sd2block;
+ else
+ sdtype = ao_sdtype_sd2byte;
+ } else {
+ sdtype = ao_sdtype_sd1;
+ }
+ }
+
+ /* For everything but SDHC cards, set the block length */
+ if (sdtype != ao_sdtype_sd2block) {
+ ret = ao_sdcard_set_blocklen(512);
+ if (ret != SDCARD_STATUS_READY_STATE)
+ DBG ("set_blocklen failed, ignoring\n");
+ }
+ }
+
+ DBG ("SD card detected, type %d\n", sdtype);
+bail:
+ ao_sdcard_put();
+}
+
+static uint8_t
+ao_sdcard_wait_block_start(void)
+{
+ int i;
+ uint8_t v;
+
+ DBG ("\twait_block_start\n");
+ for (i = 0; i < SDCARD_BLOCK_TIMEOUT; i++) {
+ ao_sdcard_recv(&v, 1);
+ DBG("\t\trecv %02x\n", v);
+ if (v != 0xff)
+ break;
+ }
+ return v;
+}
+
+/*
+ * Read a block of 512 bytes from the card
+ */
+uint8_t
+ao_sdcard_read_block(uint32_t block, uint8_t *data)
+{
+ uint8_t ret;
+ uint8_t crc[2];
+
+ ao_sdcard_lock();
+ if (!initialized) {
+ ao_sdcard_setup();
+ initialized = 1;
+ if (sdtype != ao_sdtype_unknown)
+ present = 1;
+ }
+ if (!present) {
+ ao_sdcard_unlock();
+ return 0;
+ }
+ if (sdtype != ao_sdtype_sd2block)
+ block <<= 9;
+ ao_sdcard_get();
+ ao_sdcard_select();
+ ret = ao_sdcard_send_cmd(SDCARD_READ_BLOCK, block);
+ ao_sdcard_recv_reply(NULL, 0);
+ if (ret != SDCARD_STATUS_READY_STATE)
+ goto bail;
+
+ if (ao_sdcard_wait_block_start() != 0xfe) {
+ ret = 0x3f;
+ goto bail;
+ }
+
+ ao_sdcard_recv(data, 512);
+ ao_sdcard_recv(crc, 2);
+bail:
+ ao_sdcard_deselect();
+ ao_sdcard_put();
+ ao_sdcard_unlock();
+ return ret == SDCARD_STATUS_READY_STATE;
+}
+
+/*
+ * Write a block of 512 bytes to the card
+ */
+uint8_t
+ao_sdcard_write_block(uint32_t block, uint8_t *data)
+{
+ /* Not doing anything until the file system code seems reasonable
+ */
+ return 1;
+}
+
+void
+ao_sdcard_init(void)
+{
+ ao_spi_init_cs(AO_SDCARD_SPI_CS_PORT, (1 << AO_SDCARD_SPI_CS_PIN));
+}
+
+
projects / fw / altos / blobdiff