[PATCH 26/30] mci: core: implement mmc_send_tuning

[Ahmad Fatoum]

For use by drivers that support eMMC standard tuning, add a new
mmc_send_tuning helper that sends 64-128 bytes and checks the result
for bit errors.

Signed-off-by: Ahmad Fatoum <a.fatoum at pengutronix.de>
---
 drivers/mci/mci-core.c | 78 ++++++++++++++++++++++++++++++++++++++++++
 include/mci.h          |  1 +
 2 files changed, 79 insertions(+)

diff --git a/drivers/mci/mci-core.c b/drivers/mci/mci-core.c
index 2645f9240d93..204143011e30 100644
--- a/drivers/mci/mci-core.c
+++ b/drivers/mci/mci-core.c
@@ -1607,6 +1607,84 @@ int mci_execute_tuning(struct mci *mci)
 	return host->ops.execute_tuning(host, opcode);
 }
 
+static const u8 tuning_blk_pattern_4bit[] = {
+	0xff, 0x0f, 0xff, 0x00, 0xff, 0xcc, 0xc3, 0xcc,
+	0xc3, 0x3c, 0xcc, 0xff, 0xfe, 0xff, 0xfe, 0xef,
+	0xff, 0xdf, 0xff, 0xdd, 0xff, 0xfb, 0xff, 0xfb,
+	0xbf, 0xff, 0x7f, 0xff, 0x77, 0xf7, 0xbd, 0xef,
+	0xff, 0xf0, 0xff, 0xf0, 0x0f, 0xfc, 0xcc, 0x3c,
+	0xcc, 0x33, 0xcc, 0xcf, 0xff, 0xef, 0xff, 0xee,
+	0xff, 0xfd, 0xff, 0xfd, 0xdf, 0xff, 0xbf, 0xff,
+	0xbb, 0xff, 0xf7, 0xff, 0xf7, 0x7f, 0x7b, 0xde,
+};
+
+static const u8 tuning_blk_pattern_8bit[] = {
+	0xff, 0xff, 0x00, 0xff, 0xff, 0xff, 0x00, 0x00,
+	0xff, 0xff, 0xcc, 0xcc, 0xcc, 0x33, 0xcc, 0xcc,
+	0xcc, 0x33, 0x33, 0xcc, 0xcc, 0xcc, 0xff, 0xff,
+	0xff, 0xee, 0xff, 0xff, 0xff, 0xee, 0xee, 0xff,
+	0xff, 0xff, 0xdd, 0xff, 0xff, 0xff, 0xdd, 0xdd,
+	0xff, 0xff, 0xff, 0xbb, 0xff, 0xff, 0xff, 0xbb,
+	0xbb, 0xff, 0xff, 0xff, 0x77, 0xff, 0xff, 0xff,
+	0x77, 0x77, 0xff, 0x77, 0xbb, 0xdd, 0xee, 0xff,
+	0xff, 0xff, 0xff, 0x00, 0xff, 0xff, 0xff, 0x00,
+	0x00, 0xff, 0xff, 0xcc, 0xcc, 0xcc, 0x33, 0xcc,
+	0xcc, 0xcc, 0x33, 0x33, 0xcc, 0xcc, 0xcc, 0xff,
+	0xff, 0xff, 0xee, 0xff, 0xff, 0xff, 0xee, 0xee,
+	0xff, 0xff, 0xff, 0xdd, 0xff, 0xff, 0xff, 0xdd,
+	0xdd, 0xff, 0xff, 0xff, 0xbb, 0xff, 0xff, 0xff,
+	0xbb, 0xbb, 0xff, 0xff, 0xff, 0x77, 0xff, 0xff,
+	0xff, 0x77, 0x77, 0xff, 0x77, 0xbb, 0xdd, 0xee,
+};
+
+int mmc_send_tuning(struct mci *mci, u32 opcode)
+{
+	struct mci_cmd cmd = {};
+	struct mci_data data = {};
+	const u8 *tuning_block_pattern;
+	int size, err = 0;
+	u8 *data_buf;
+
+	if (mci->host->ios.bus_width == MMC_BUS_WIDTH_8) {
+		tuning_block_pattern = tuning_blk_pattern_8bit;
+		size = sizeof(tuning_blk_pattern_8bit);
+	} else if (mci->host->ios.bus_width == MMC_BUS_WIDTH_4) {
+		tuning_block_pattern = tuning_blk_pattern_4bit;
+		size = sizeof(tuning_blk_pattern_4bit);
+	} else
+		return -EINVAL;
+
+	data_buf = calloc(size, 1);
+	if (!data_buf)
+		return -ENOMEM;
+
+	mci_setup_cmd(&cmd, opcode, 0, MMC_RSP_R1 | MMC_CMD_ADTC);
+
+
+	data.blocksize = size;
+	data.blocks = 1;
+	data.flags = MMC_DATA_READ;
+
+	/*
+	 * According to the tuning specs, Tuning process
+	 * is normally shorter 40 executions of CMD19,
+	 * and timeout value should be shorter than 150 ms
+	 */
+	data.timeout_ns = 150 * NSEC_PER_MSEC;
+
+	err = mci_send_cmd(mci, &cmd, &data);
+	if (err)
+		goto out;
+
+	if (memcmp(data_buf, tuning_block_pattern, size))
+		err = -EIO;
+
+out:
+	free(data_buf);
+	return err;
+}
+EXPORT_SYMBOL_GPL(mmc_send_tuning);
+
 int mci_send_abort_tuning(struct mci *mci, u32 opcode)
 {
 	struct mci_cmd cmd = {};
diff --git a/include/mci.h b/include/mci.h
index 29aaecb46305..207fb9779a14 100644
--- a/include/mci.h
+++ b/include/mci.h
@@ -773,6 +773,7 @@ static inline int mmc_card_hs(struct mci *mci)
  */
 int mmc_hs200_tuning(struct mci *mci);
 int mci_execute_tuning(struct mci *mci);
+int mmc_send_tuning(struct mci *mci, u32 opcode);
 int mci_send_abort_tuning(struct mci *mci, u32 opcode);
 int mmc_select_timing(struct mci *mci);
 int mci_set_blockcount(struct mci *mci, unsigned int cmdarg);
-- 
2.39.5