The arasan SDHCI driver doesn't use MMC tuning but SDHCI tuning. Both
are not supported yet in barebox.
Add SDHCI tuning support from linux v6.7.

Signed-off-by: Steffen Trumtrar <s.trumt...@pengutronix.de>
Signed-off-by: Ahmad Fatoum <a.fat...@pengutronix.de>
---
 drivers/mci/sdhci.c | 275 +++++++++++++++++++++++++++++++++++++++++++++++++++-
 drivers/mci/sdhci.h |  27 ++++++
 2 files changed, 301 insertions(+), 1 deletion(-)

diff --git a/drivers/mci/sdhci.c b/drivers/mci/sdhci.c
index edb819d66d..7dedd5a7b2 100644
--- a/drivers/mci/sdhci.c
+++ b/drivers/mci/sdhci.c
@@ -9,6 +9,227 @@
 
 #include "sdhci.h"
 
+#define MAX_TUNING_LOOP 40
+#define  SDHCI_MAKE_BLKSZ(dma, blksz) (((dma & 0x7) << 12) | (blksz & 0xFFF))
+
+enum sdhci_reset_reason {
+       SDHCI_RESET_FOR_INIT,
+       SDHCI_RESET_FOR_REQUEST_ERROR,
+       SDHCI_RESET_FOR_REQUEST_ERROR_DATA_ONLY,
+       SDHCI_RESET_FOR_TUNING_ABORT,
+       SDHCI_RESET_FOR_CARD_REMOVED,
+       SDHCI_RESET_FOR_CQE_RECOVERY,
+};
+
+static void sdhci_reset_for_reason(struct sdhci *host, enum sdhci_reset_reason 
reason)
+{
+       if (host->quirks2 & SDHCI_QUIRK2_ISSUE_CMD_DAT_RESET_TOGETHER) {
+               sdhci_reset(host, SDHCI_RESET_CMD | SDHCI_RESET_DATA);
+               return;
+       }
+
+       switch (reason) {
+       case SDHCI_RESET_FOR_INIT:
+               sdhci_reset(host, SDHCI_RESET_CMD | SDHCI_RESET_DATA);
+               break;
+       case SDHCI_RESET_FOR_REQUEST_ERROR:
+       case SDHCI_RESET_FOR_TUNING_ABORT:
+       case SDHCI_RESET_FOR_CARD_REMOVED:
+       case SDHCI_RESET_FOR_CQE_RECOVERY:
+               sdhci_reset(host, SDHCI_RESET_CMD);
+               sdhci_reset(host, SDHCI_RESET_DATA);
+               break;
+       case SDHCI_RESET_FOR_REQUEST_ERROR_DATA_ONLY:
+               sdhci_reset(host, SDHCI_RESET_DATA);
+               break;
+       }
+}
+
+#define sdhci_reset_for(h, r) sdhci_reset_for_reason((h), SDHCI_RESET_FOR_##r)
+
+static int sdhci_send_command_retry(struct sdhci *host, struct mci_cmd *cmd)
+{
+       int timeout = 10;
+
+       while ((sdhci_read32(host, SDHCI_PRESENT_STATE) & 
SDHCI_CMD_INHIBIT_CMD)) {
+               if (!timeout--)
+                       return -ETIMEDOUT;
+
+               mdelay(1);
+       }
+
+       return host->mci->send_cmd(host->mci, cmd, NULL);
+}
+
+/*
+ * We use sdhci_send_tuning() because mmc_send_tuning() is not a good fit. 
SDHCI
+ * tuning command does not have a data payload (or rather the hardware does it
+ * automatically) so mmc_send_tuning() will return -EIO. Also the tuning 
command
+ * interrupt setup is different to other commands and there is no timeout
+ * interrupt so special handling is needed.
+ */
+static int sdhci_send_tuning(struct sdhci *host, u32 opcode)
+{
+       struct mci_cmd cmd = {};
+       int ret;
+
+       cmd.cmdidx = opcode;
+       cmd.resp_type = MMC_RSP_R1 | MMC_CMD_ADTC;
+
+       /*
+        * In response to CMD19, the card sends 64 bytes of tuning
+        * block to the Host Controller. So we set the block size
+        * to 64 here.
+        */
+       if (cmd.cmdidx == MMC_SEND_TUNING_BLOCK_HS200 &&
+           host->mci->bus_width == MMC_BUS_WIDTH_8) {
+               sdhci_write16(host, SDHCI_BLOCK_SIZE, SDHCI_MAKE_BLKSZ(7, 128));
+       } else {
+               sdhci_write16(host, SDHCI_BLOCK_SIZE, SDHCI_MAKE_BLKSZ(7, 64));
+       }
+
+       ret = sdhci_send_command_retry(host, &cmd);
+
+       return ret;
+}
+
+static void sdhci_end_tuning(struct sdhci *host)
+{
+       sdhci_write32(host, SDHCI_INT_ENABLE, host->tuning_old_ier);
+       sdhci_write32(host, SDHCI_SIGNAL_ENABLE, host->tuning_old_sig);
+}
+
+static void sdhci_start_tuning(struct sdhci *host)
+{
+       u16 ctrl;
+
+       ctrl = sdhci_read16(host, SDHCI_HOST_CONTROL2);
+       ctrl |= SDHCI_CTRL_EXEC_TUNING;
+       sdhci_write16(host, SDHCI_HOST_CONTROL2, ctrl);
+
+       mdelay(1);
+
+       host->tuning_old_ier = sdhci_read32(host, SDHCI_INT_ENABLE);
+       host->tuning_old_sig = sdhci_read32(host, SDHCI_SIGNAL_ENABLE);
+
+       sdhci_write32(host, SDHCI_INT_ENABLE, SDHCI_INT_DATA_AVAIL);
+       sdhci_write32(host, SDHCI_SIGNAL_ENABLE, SDHCI_INT_DATA_AVAIL);
+}
+
+static void sdhci_reset_tuning(struct sdhci *host)
+{
+       u16 ctrl;
+
+       ctrl = sdhci_read16(host, SDHCI_HOST_CONTROL2);
+       ctrl &= ~SDHCI_CTRL_TUNED_CLK;
+       ctrl &= ~SDHCI_CTRL_EXEC_TUNING;
+       sdhci_write16(host, SDHCI_HOST_CONTROL2, ctrl);
+}
+
+static void sdhci_abort_tuning(struct sdhci *host, u32 opcode)
+{
+       sdhci_reset_tuning(host);
+
+       sdhci_reset_for(host, TUNING_ABORT);
+
+       sdhci_end_tuning(host);
+
+       mci_send_abort_tuning(host->mci->mci, opcode);
+}
+
+static int __sdhci_execute_tuning(struct sdhci *host, u32 opcode)
+{
+       int i;
+       int ret;
+
+       /*
+        * Issue opcode repeatedly till Execute Tuning is set to 0 or the number
+        * of loops reaches tuning loop count.
+        * Some controllers are known to always require 40 iterations.
+        */
+       for (i = 0; i < host->tuning_loop_count; i++) {
+               u16 ctrl;
+
+               ret = sdhci_send_tuning(host, opcode);
+               if (ret) {
+                       sdhci_abort_tuning(host, opcode);
+                       return -ETIMEDOUT;
+               }
+
+               /* Spec does not require a delay between tuning cycles */
+               if (host->tuning_delay > 0)
+                       mdelay(host->tuning_delay);
+
+               ctrl = sdhci_read16(host, SDHCI_HOST_CONTROL2);
+               if (!(ctrl & SDHCI_CTRL_EXEC_TUNING)) {
+                       if (ctrl & SDHCI_CTRL_TUNED_CLK) {
+                               return 0; /* Success! */
+                       }
+                       break;
+               }
+
+       }
+
+       dev_dbg(&host->mci->mci->dev, "Tuning timeout, falling back to fixed 
sampling clock\n");
+       sdhci_reset_tuning(host);
+       return -EAGAIN;
+}
+
+int sdhci_execute_tuning(struct sdhci *sdhci, u32 opcode)
+{
+       struct mci_host *host = sdhci->mci;
+       int err = 0;
+       unsigned int tuning_count = 0;
+
+       if (sdhci->tuning_mode == SDHCI_TUNING_MODE_1)
+               tuning_count = sdhci->tuning_count;
+
+       /*
+        * The Host Controller needs tuning in case of SDR104 and DDR50
+        * mode, and for SDR50 mode when Use Tuning for SDR50 is set in
+        * the Capabilities register.
+        * If the Host Controller supports the HS200 mode then the
+        * tuning function has to be executed.
+        */
+       switch (host->timing) {
+       /* HS400 tuning is done in HS200 mode */
+       case MMC_TIMING_MMC_HS400:
+               err = -EINVAL;
+               goto out;
+
+       case MMC_TIMING_MMC_HS200:
+               break;
+
+       case MMC_TIMING_UHS_SDR104:
+       case MMC_TIMING_UHS_DDR50:
+               break;
+
+       case MMC_TIMING_UHS_SDR50:
+               fallthrough;
+
+       default:
+               goto out;
+       }
+
+       if (sdhci->platform_execute_tuning) {
+               err = sdhci->platform_execute_tuning(host, opcode);
+               goto out;
+       }
+
+       if (sdhci->tuning_delay < 0)
+               sdhci->tuning_delay = opcode == MMC_SEND_TUNING_BLOCK;
+
+       sdhci_start_tuning(sdhci);
+
+       sdhci->tuning_err = __sdhci_execute_tuning(sdhci, opcode);
+
+       sdhci_end_tuning(sdhci);
+out:
+
+       return err;
+}
+EXPORT_SYMBOL_GPL(sdhci_execute_tuning);
+
 void sdhci_read_response(struct sdhci *sdhci, struct mci_cmd *cmd)
 {
        if (cmd->resp_type & MMC_RSP_136) {
@@ -50,7 +271,12 @@ void sdhci_set_cmd_xfer_mode(struct sdhci *host, struct 
mci_cmd *cmd,
 
        *command |= SDHCI_CMD_INDEX(cmd->cmdidx);
 
-       if (data) {
+       if (cmd->cmdidx == MMC_SEND_TUNING_BLOCK ||
+           cmd->cmdidx == MMC_SEND_TUNING_BLOCK_HS200) {
+               *command |= SDHCI_DATA_PRESENT;
+               *xfer = SDHCI_DATA_TO_HOST;
+
+       } else if (data) {
                *command |= SDHCI_DATA_PRESENT;
 
                *xfer |= SDHCI_BLOCK_COUNT_EN;
@@ -111,6 +337,31 @@ void sdhci_set_bus_width(struct sdhci *host, int width)
        sdhci_write8(host, SDHCI_HOST_CONTROL, ctrl);
 }
 
+static void sdhci_set_uhs_signaling(struct sdhci *host, unsigned timing)
+{
+       u16 ctrl_2;
+
+       ctrl_2 = sdhci_read16(host, SDHCI_HOST_CONTROL2);
+       /* Select Bus Speed Mode for host */
+       ctrl_2 &= ~SDHCI_CTRL_UHS_MASK;
+       if ((timing == MMC_TIMING_MMC_HS200) ||
+           (timing == MMC_TIMING_UHS_SDR104))
+               ctrl_2 |= SDHCI_CTRL_UHS_SDR104;
+       else if (timing == MMC_TIMING_UHS_SDR12)
+               ctrl_2 |= SDHCI_CTRL_UHS_SDR12;
+       else if (timing == MMC_TIMING_UHS_SDR25)
+               ctrl_2 |= SDHCI_CTRL_UHS_SDR25;
+       else if (timing == MMC_TIMING_UHS_SDR50)
+               ctrl_2 |= SDHCI_CTRL_UHS_SDR50;
+       else if ((timing == MMC_TIMING_UHS_DDR50) ||
+                (timing == MMC_TIMING_MMC_DDR52))
+               ctrl_2 |= SDHCI_CTRL_UHS_DDR50;
+       else if (timing == MMC_TIMING_MMC_HS400)
+               ctrl_2 |= SDHCI_CTRL_HS400; /* Non-standard */
+       sdhci_write16(host, SDHCI_HOST_CONTROL2, ctrl_2);
+}
+EXPORT_SYMBOL_GPL(sdhci_set_uhs_signaling);
+
 static inline bool sdhci_can_64bit_dma(struct sdhci *host)
 {
        /*
@@ -567,6 +818,8 @@ void sdhci_set_clock(struct sdhci *host, unsigned int 
clock, unsigned int input_
 
        host->mci->clock = 0;
 
+       sdhci_set_uhs_signaling(host, host->mci->timing);
+
        sdhci_wait_idle(host, NULL);
 
        sdhci_write16(host, SDHCI_CLOCK_CONTROL, 0);
@@ -695,5 +948,25 @@ int sdhci_setup_host(struct sdhci *host)
        if (sdhci_can_64bit_dma(host))
                host->flags |= SDHCI_USE_64_BIT_DMA;
 
+       if ((mci->caps2 & (MMC_CAP2_HS200_1_8V_SDR | MMC_CAP2_HS400_1_8V)))
+               host->flags |= SDHCI_SIGNALING_180;
+
+       host->tuning_delay = -1;
+       host->tuning_loop_count = MAX_TUNING_LOOP;
+
+       /* Initial value for re-tuning timer count */
+       host->tuning_count = FIELD_GET(SDHCI_RETUNING_TIMER_COUNT_MASK,
+                                      host->caps1);
+
+       /*
+        * In case Re-tuning Timer is not disabled, the actual value of
+        * re-tuning timer will be 2 ^ (n - 1).
+        */
+       if (host->tuning_count)
+               host->tuning_count = 1 << (host->tuning_count - 1);
+
+       /* Re-tuning mode supported by the Host Controller */
+       host->tuning_mode = FIELD_GET(SDHCI_RETUNING_MODE_MASK, host->caps1);
+
        return 0;
 }
diff --git a/drivers/mci/sdhci.h b/drivers/mci/sdhci.h
index 2139498855..f10a801c88 100644
--- a/drivers/mci/sdhci.h
+++ b/drivers/mci/sdhci.h
@@ -28,9 +28,11 @@
 #define SDHCI_TRANSFER_MODE                                    0x0c
 #define  SDHCI_MULTIPLE_BLOCKS                 BIT(5)
 #define  SDHCI_DATA_TO_HOST                    BIT(4)
+#define  SDHCI_TRNS_AUTO_CMD12                 BIT(3)
 #define  SDHCI_BLOCK_COUNT_EN                  BIT(1)
 #define  SDHCI_DMA_EN                          BIT(0)
 #define SDHCI_COMMAND                                          0x0e
+#define  SDHCI_MAKE_CMD(c, f)                  (((c & 0xff) << 8) | (f & 0xff))
 #define  SDHCI_CMD_INDEX(c)                    (((c) & 0x3f) << 8)
 #define  SDHCI_COMMAND_CMDTYP_SUSPEND          (1 << 6)
 #define  SDHCI_COMMAND_CMDTYP_RESUME           (2 << 6)
@@ -121,6 +123,15 @@
 #define SDHCI_SIGNAL_ENABLE                                    0x38
 #define SDHCI_ACMD12_ERR__HOST_CONTROL2                                0x3C
 #define SDHCI_HOST_CONTROL2                                    0x3E
+#define  SDHCI_CTRL_UHS_MASK                   GENMASK(3, 0)
+#define   SDHCI_CTRL_UHS_SDR12                 0x0
+#define   SDHCI_CTRL_UHS_SDR25                 0x1
+#define   SDHCI_CTRL_UHS_SDR50                 0x2
+#define   SDHCI_CTRL_UHS_SDR104                        0x3
+#define   SDHCI_CTRL_UHS_DDR50                 0x4
+#define   SDHCI_CTRL_HS400                     0x5 /* Non-standard */
+#define  SDHCI_CTRL_EXEC_TUNING                        BIT(6)
+#define  SDHCI_CTRL_TUNED_CLK                  BIT(7)
 #define  SDHCI_CTRL_64BIT_ADDR                 BIT(13)
 #define  SDHCI_CTRL_V4_MODE                    BIT(12)
 #define SDHCI_CAPABILITIES                                     0x40
@@ -225,12 +236,27 @@ struct sdhci {
 #define SDHCI_QUIRK_MISSING_CAPS               BIT(27)
        unsigned int quirks2;
 #define SDHCI_QUIRK2_CLOCK_DIV_ZERO_BROKEN     BIT(15)
+#define SDHCI_QUIRK2_ISSUE_CMD_DAT_RESET_TOGETHER      BIT(19)
        u32 caps;       /* CAPABILITY_0 */
        u32 caps1;      /* CAPABILITY_1 */
        bool read_caps; /* Capability flags have been read */
        u32 sdma_boundary;
 
+       unsigned int            tuning_count;   /* Timer count for re-tuning */
+       unsigned int            tuning_mode;    /* Re-tuning mode supported by 
host */
+       unsigned int            tuning_err;     /* Error code for re-tuning */
+#define SDHCI_TUNING_MODE_1    0
+#define SDHCI_TUNING_MODE_2    1
+#define SDHCI_TUNING_MODE_3    2
+       /* Delay (ms) between tuning commands */
+       int                     tuning_delay;
+       int                     tuning_loop_count;
+       int                     tuning_old_ier;
+       int                     tuning_old_sig;
+
        struct mci_host *mci;
+
+       int (*platform_execute_tuning)(struct mci_host *host, u32 opcode);
 };
 
 static inline u32 sdhci_read32(struct sdhci *host, int reg)
@@ -282,6 +308,7 @@ static inline void sdhci_write8(struct sdhci *host, int 
reg, u32 val)
 }
 
 #define SDHCI_NO_DMA DMA_ERROR_CODE
+int sdhci_execute_tuning(struct sdhci *sdhci, u32 opcode);
 int sdhci_wait_idle(struct sdhci *host, struct mci_cmd *cmd);
 int sdhci_wait_for_done(struct sdhci *host, u32 mask);
 void sdhci_read_response(struct sdhci *host, struct mci_cmd *cmd);

-- 
2.40.1


Reply via email to