From: Wan Zongshun <Vincent.Wan@xxxxxxx>
This patch is to add software tuning functions for AMD hs200
mode.
Signed-off-by: Wan Zongshun <Vincent.Wan@xxxxxxx>
---
drivers/mmc/host/sdhci-pci-core.c | 146 ++++++++++++++++++++++++++++++++++++++
1 file changed, 146 insertions(+)
diff --git a/drivers/mmc/host/sdhci-pci-core.c b/drivers/mmc/host/sdhci-pci-core.c
index 08f4a9f..01c5723 100644
--- a/drivers/mmc/host/sdhci-pci-core.c
+++ b/drivers/mmc/host/sdhci-pci-core.c
@@ -729,6 +729,152 @@ enum amd_chipset_gen {
AMD_CHIPSET_UNKNOWN,
};
+struct tuning_descriptor {
+ unsigned char tune_around;
+ bool this_tune_ok;
+ bool last_tune_ok;
+ bool valid_front_end;
+ unsigned char valid_front;
+ unsigned char valid_window_max;
+ unsigned char tune_low_max;
+ unsigned char tune_low;
+ unsigned char valid_window;
+ unsigned char tune_result;
+};
+
+#define AMD_EMMC_TUNE_REG 0xb8
+static struct tuning_descriptor tdescriptor;
+
+static int 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 config_tuning_phase(struct sdhci_host *host, unsigned char 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, AMD_EMMC_TUNE_REG, &val);
+ val &= ~0xf;
+ val |= (0x10800 | phase);
+ pci_write_config_dword(pdev, AMD_EMMC_TUNE_REG, val);
+
+ spin_unlock_irqrestore(&host->lock, flags);
+
+ return 0;
+}
+
+static int find_good_phase(struct sdhci_host *host)
+{
+ struct tuning_descriptor *td = &tdescriptor;
+ 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);
+
+ if (td->this_tune_ok == false)
+ td->valid_front_end = 1;
+
+ if (td->valid_front_end)
+ td->valid_front = td->valid_front;
+ else if (td->this_tune_ok)
+ td->valid_front = 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) {
+ if (!td->last_tune_ok)
+ td->tune_low = td->tune_around;
+ td->valid_window = td->valid_window + 1;
+ } else {
+ if (td->last_tune_ok)
+ td->valid_window = 0x0;
+ }
+
+ 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, AMD_EMMC_TUNE_REG, &val);
+ val &= ~0xf;
+ val |= (0x10800 | td->tune_result);
+ pci_write_config_dword(pdev, AMD_EMMC_TUNE_REG, val);
+ }
+
+ spin_unlock_irqrestore(&host->lock, flags);
+
+ return 0;
+}
+
+static int amd_execute_tuning(struct sdhci_host *host, u32 opcode)
+{
+ struct tuning_descriptor *td = &tdescriptor;
+
+ tuning_reset(host);
+
+ for (td->tune_around = 0; td->tune_around < 12; td->tune_around++) {
+
+ 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);
+ } else {
+ td->this_tune_ok = true;
+ }
+
+ find_good_phase(host);
+ }
+
+ host->mmc->retune_period = 0;
+
+ return 0;
+}
+
static int amd_probe(struct sdhci_pci_chip *chip)
{
struct pci_dev *smbus_dev;
--
1.9.1
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