This patch adds support for HS200 tuning mode, on AMD eMMC-4.5.1
Made changes to the earlier submission based on the comments
received from Adrian.
Also re-spinned to the latest version based on feedback from Ulf.
Reviewed-by: Sen, Pankaj <Pankaj.Sen@xxxxxxx>
Reviewed-by: Shah, Nehal-bakulchandra <Nehal-bakulchandra.Shah@xxxxxxx>
Signed-off-by: S-k, Shyam-sundar <Shyam-sundar.S-k@xxxxxxx>
---
drivers/mmc/host/sdhci-pci-core.c | 178 +++++++++++++++++++++++++++++++++++++-
1 file changed, 177 insertions(+), 1 deletion(-)
diff --git a/drivers/mmc/host/sdhci-pci-core.c b/drivers/mmc/host/sdhci-pci-core.c
index 782c8d2..9576f82 100644
--- a/drivers/mmc/host/sdhci-pci-core.c
+++ b/drivers/mmc/host/sdhci-pci-core.c
@@ -817,6 +817,171 @@ enum amd_chipset_gen {
AMD_CHIPSET_UNKNOWN,
};
+static const struct sdhci_ops amd_sdhci_pci_ops;
+
+struct amd_tuning_descriptor {
+ u8 tune_around;
+ bool this_tune_ok;
+ bool last_tune_ok;
+ u8 valid_front;
+ u8 valid_window_max;
+ u8 tune_low_max;
+ u8 tune_low;
+ u8 valid_window;
+ u8 tune_result;
+};
+
+static int amd_tuning_reset(struct sdhci_host *host)
+{
+ unsigned int val;
+ unsigned long flags;
+
+ spin_lock_irqsave(&host->lock, flags);
+
+ val = sdhci_readw(host, SDHCI_HOST_CONTROL2);
+ val |= SDHCI_CTRL_PRESET_VAL_ENABLE | SDHCI_CTRL_EXEC_TUNING;
+ sdhci_writew(host, val, SDHCI_HOST_CONTROL2);
+
+ val = sdhci_readw(host, SDHCI_HOST_CONTROL2);
+ val &= ~SDHCI_CTRL_EXEC_TUNING;
+ sdhci_writew(host, val, SDHCI_HOST_CONTROL2);
+
+ spin_unlock_irqrestore(&host->lock, flags);
+
+ return 0;
+}
+
+static int amd_config_tuning_phase(struct sdhci_host *host, u8 phase)
+{
+ struct sdhci_pci_slot *slot = sdhci_priv(host);
+ struct pci_dev *pdev = slot->chip->pdev;
+ unsigned int val;
+ unsigned long flags;
+
+ spin_lock_irqsave(&host->lock, flags);
+
+ pci_read_config_dword(pdev, 0xb8, &val);
+ val &= ~0x1f;
+ val |= (0x10800 | (phase << 1));
+ pci_write_config_dword(pdev, 0xb8, val);
+
+ spin_unlock_irqrestore(&host->lock, flags);
+
+ return 0;
+}
+
+static int amd_find_good_phase(struct sdhci_host *host)
+{
+ struct sdhci_pci_slot *slot = sdhci_priv(host);
+ struct pci_dev *pdev = slot->chip->pdev;
+ struct amd_tuning_descriptor *td = sdhci_pci_priv(slot);
+
+ unsigned int val;
+ unsigned long flags;
+
+ spin_lock_irqsave(&host->lock, flags);
+
+ if (td->this_tune_ok)
+ td->valid_front += 1;
+ if ((!td->this_tune_ok && td->last_tune_ok) ||
+ (td->tune_around == 11)) {
+ if (td->valid_window > td->valid_window_max) {
+ td->valid_window_max = td->valid_window;
+ td->tune_low_max = td->tune_low;
+ }
+ }
+ if (td->this_tune_ok && (!td->last_tune_ok))
+ td->tune_low = td->tune_around;
+ if (!td->this_tune_ok && td->last_tune_ok)
+ td->valid_window = 0;
+ else if (td->this_tune_ok)
+ td->valid_window += 1;
+
+ td->last_tune_ok = td->this_tune_ok;
+
+ if (td->tune_around == 11) {
+ if ((td->valid_front + td->valid_window) >
+ td->valid_window_max) {
+ if (td->valid_front > td->valid_window)
+ td->tune_result = ((td->valid_front -
+ td->valid_window) >> 1);
+ else
+ td->tune_result = td->tune_low +
+ ((td->valid_window + td->valid_front) >> 1);
+ } else {
+ td->tune_result = td->tune_low_max +
+ (td->valid_window_max >> 1);
+ }
+
+ if (td->tune_result > 0x0b)
+ td->tune_result = 0x0b;
+
+ pci_read_config_dword(pdev, 0xb8, &val);
+ val &= ~0x1f;
+ val |= (0x10800 | (td->tune_result << 1));
+ pci_write_config_dword(pdev, 0xb8, val);
+ }
+
+ spin_unlock_irqrestore(&host->lock, flags);
+
+ return 0;
+}
+
+static int amd_enable_manual_tuning(struct sdhci_pci_slot *slot)
+{
+ struct pci_dev *pdev = slot->chip->pdev;
+ unsigned int val;
+
+ pci_read_config_dword(pdev, 0xd0, &val);
+ val &= 0xffffffcf;
+ val |= 0x30;
+ pci_write_config_dword(pdev, 0xd0, val);
+
+ return 0;
+}
+
+static int amd_execute_tuning(struct sdhci_host *host, u32 opcode)
+{
+ struct sdhci_pci_slot *slot = sdhci_priv(host);
+ struct amd_tuning_descriptor *td = sdhci_pci_priv(slot);
+ u8 ctrl;
+
+ amd_tuning_reset(host);
+ memset(td, 0, sizeof(struct amd_tuning_descriptor));
+
+ /*********************************************************************/
+ /* Enabling Software Tuning */
+ /********************************************************************/
+ /* 1. First switch the eMMC to HS200 Mode
+ * 2. Prepare the registers by using the sampling clock select
+ * 3. Send the CMD21 12 times with block length of 64 bytes
+ * 4. Everytime change the clk phase and check for CRC error
+ * (CMD and DATA),if error, soft reset the CMD and DATA line
+ * 5. Calculate the window and set the clock phase.
+ */
+
+ for (td->tune_around = 0; td->tune_around < 12; td->tune_around++) {
+ amd_config_tuning_phase(host, td->tune_around);
+
+ if (mmc_send_tuning(host->mmc, opcode, NULL)) {
+ td->this_tune_ok = false;
+ host->mmc->need_retune = 0;
+ mdelay(4);
+ ctrl = SDHCI_RESET_CMD | SDHCI_RESET_DATA;
+ sdhci_writeb(host, ctrl, SDHCI_SOFTWARE_RESET);
+ } else {
+ td->this_tune_ok = true;
+ }
+
+ amd_find_good_phase(host);
+ }
+
+ host->mmc->retune_period = 0;
+
+ amd_enable_manual_tuning(slot);
+ return 0;
+}
+
static int amd_probe(struct sdhci_pci_chip *chip)
{
struct pci_dev *smbus_dev;
@@ -841,7 +1006,6 @@ static int amd_probe(struct sdhci_pci_chip *chip)
if ((gen == AMD_CHIPSET_BEFORE_ML) || (gen == AMD_CHIPSET_CZ)) {
chip->quirks2 |= SDHCI_QUIRK2_CLEAR_TRANSFERMODE_REG_BEFORE_CMD;
- chip->quirks2 |= SDHCI_QUIRK2_BROKEN_HS200;
}
return 0;
@@ -849,6 +1013,7 @@ static int amd_probe(struct sdhci_pci_chip *chip)
static const struct sdhci_pci_fixes sdhci_amd = {
.probe = amd_probe,
+ .ops = &amd_sdhci_pci_ops,
};
static const struct pci_device_id pci_ids[] = {
@@ -1469,6 +1634,17 @@ static const struct sdhci_ops sdhci_pci_ops = {
.select_drive_strength = sdhci_pci_select_drive_strength,
};
+static const struct sdhci_ops amd_sdhci_pci_ops = {
+ .set_clock = sdhci_set_clock,
+ .enable_dma = sdhci_pci_enable_dma,
+ .set_bus_width = sdhci_pci_set_bus_width,
+ .reset = sdhci_reset,
+ .set_uhs_signaling = sdhci_set_uhs_signaling,
+ .hw_reset = sdhci_pci_hw_reset,
+ .select_drive_strength = sdhci_pci_select_drive_strength,
+ .platform_execute_tuning = amd_execute_tuning,
+};
+
/*****************************************************************************\
* *
* Suspend/resume *
--
2.7.4
--
To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
