dmaengine: at_hdmac: Start transfer for cyclic channels in issue_pending
[platform/kernel/linux-rpi.git] / drivers / spi / spi-fsi.c
index 87f8829..829770b 100644 (file)
 
 #define SPI_FSI_BASE                   0x70000
 #define SPI_FSI_INIT_TIMEOUT_MS                1000
-#define SPI_FSI_MAX_XFR_SIZE           2048
-#define SPI_FSI_MAX_XFR_SIZE_RESTRICTED        8
+#define SPI_FSI_MAX_RX_SIZE            8
+#define SPI_FSI_MAX_TX_SIZE            40
 
 #define SPI_FSI_ERROR                  0x0
 #define SPI_FSI_COUNTER_CFG            0x1
-#define  SPI_FSI_COUNTER_CFG_LOOPS(x)   (((u64)(x) & 0xffULL) << 32)
-#define  SPI_FSI_COUNTER_CFG_N2_RX      BIT_ULL(8)
-#define  SPI_FSI_COUNTER_CFG_N2_TX      BIT_ULL(9)
-#define  SPI_FSI_COUNTER_CFG_N2_IMPLICIT BIT_ULL(10)
-#define  SPI_FSI_COUNTER_CFG_N2_RELOAD  BIT_ULL(11)
 #define SPI_FSI_CFG1                   0x2
 #define SPI_FSI_CLOCK_CFG              0x3
 #define  SPI_FSI_CLOCK_CFG_MM_ENABLE    BIT_ULL(32)
@@ -76,8 +71,6 @@ struct fsi_spi {
        struct device *dev;     /* SPI controller device */
        struct fsi_device *fsi; /* FSI2SPI CFAM engine device */
        u32 base;
-       size_t max_xfr_size;
-       bool restricted;
 };
 
 struct fsi_spi_sequence {
@@ -241,7 +234,7 @@ static int fsi_spi_reset(struct fsi_spi *ctx)
        return fsi_spi_write_reg(ctx, SPI_FSI_STATUS, 0ULL);
 }
 
-static int fsi_spi_sequence_add(struct fsi_spi_sequence *seq, u8 val)
+static void fsi_spi_sequence_add(struct fsi_spi_sequence *seq, u8 val)
 {
        /*
         * Add the next byte of instruction to the 8-byte sequence register.
@@ -251,8 +244,6 @@ static int fsi_spi_sequence_add(struct fsi_spi_sequence *seq, u8 val)
         */
        seq->data |= (u64)val << seq->bit;
        seq->bit -= 8;
-
-       return ((64 - seq->bit) / 8) - 2;
 }
 
 static void fsi_spi_sequence_init(struct fsi_spi_sequence *seq)
@@ -261,71 +252,11 @@ static void fsi_spi_sequence_init(struct fsi_spi_sequence *seq)
        seq->data = 0ULL;
 }
 
-static int fsi_spi_sequence_transfer(struct fsi_spi *ctx,
-                                    struct fsi_spi_sequence *seq,
-                                    struct spi_transfer *transfer)
-{
-       int loops;
-       int idx;
-       int rc;
-       u8 val = 0;
-       u8 len = min(transfer->len, 8U);
-       u8 rem = transfer->len % len;
-
-       loops = transfer->len / len;
-
-       if (transfer->tx_buf) {
-               val = SPI_FSI_SEQUENCE_SHIFT_OUT(len);
-               idx = fsi_spi_sequence_add(seq, val);
-
-               if (rem)
-                       rem = SPI_FSI_SEQUENCE_SHIFT_OUT(rem);
-       } else if (transfer->rx_buf) {
-               val = SPI_FSI_SEQUENCE_SHIFT_IN(len);
-               idx = fsi_spi_sequence_add(seq, val);
-
-               if (rem)
-                       rem = SPI_FSI_SEQUENCE_SHIFT_IN(rem);
-       } else {
-               return -EINVAL;
-       }
-
-       if (ctx->restricted && loops > 1) {
-               dev_warn(ctx->dev,
-                        "Transfer too large; no branches permitted.\n");
-               return -EINVAL;
-       }
-
-       if (loops > 1) {
-               u64 cfg = SPI_FSI_COUNTER_CFG_LOOPS(loops - 1);
-
-               fsi_spi_sequence_add(seq, SPI_FSI_SEQUENCE_BRANCH(idx));
-
-               if (transfer->rx_buf)
-                       cfg |= SPI_FSI_COUNTER_CFG_N2_RX |
-                               SPI_FSI_COUNTER_CFG_N2_TX |
-                               SPI_FSI_COUNTER_CFG_N2_IMPLICIT |
-                               SPI_FSI_COUNTER_CFG_N2_RELOAD;
-
-               rc = fsi_spi_write_reg(ctx, SPI_FSI_COUNTER_CFG, cfg);
-               if (rc)
-                       return rc;
-       } else {
-               fsi_spi_write_reg(ctx, SPI_FSI_COUNTER_CFG, 0ULL);
-       }
-
-       if (rem)
-               fsi_spi_sequence_add(seq, rem);
-
-       return 0;
-}
-
 static int fsi_spi_transfer_data(struct fsi_spi *ctx,
                                 struct spi_transfer *transfer)
 {
        int rc = 0;
        u64 status = 0ULL;
-       u64 cfg = 0ULL;
 
        if (transfer->tx_buf) {
                int nb;
@@ -363,16 +294,6 @@ static int fsi_spi_transfer_data(struct fsi_spi *ctx,
                u64 in = 0ULL;
                u8 *rx = transfer->rx_buf;
 
-               rc = fsi_spi_read_reg(ctx, SPI_FSI_COUNTER_CFG, &cfg);
-               if (rc)
-                       return rc;
-
-               if (cfg & SPI_FSI_COUNTER_CFG_N2_IMPLICIT) {
-                       rc = fsi_spi_write_reg(ctx, SPI_FSI_DATA_TX, 0);
-                       if (rc)
-                               return rc;
-               }
-
                while (transfer->len > recv) {
                        do {
                                rc = fsi_spi_read_reg(ctx, SPI_FSI_STATUS,
@@ -439,6 +360,10 @@ static int fsi_spi_transfer_init(struct fsi_spi *ctx)
                }
        } while (seq_state && (seq_state != SPI_FSI_STATUS_SEQ_STATE_IDLE));
 
+       rc = fsi_spi_write_reg(ctx, SPI_FSI_COUNTER_CFG, 0ULL);
+       if (rc)
+               return rc;
+
        rc = fsi_spi_read_reg(ctx, SPI_FSI_CLOCK_CFG, &clock_cfg);
        if (rc)
                return rc;
@@ -459,6 +384,7 @@ static int fsi_spi_transfer_one_message(struct spi_controller *ctlr,
 {
        int rc;
        u8 seq_slave = SPI_FSI_SEQUENCE_SEL_SLAVE(mesg->spi->chip_select + 1);
+       unsigned int len;
        struct spi_transfer *transfer;
        struct fsi_spi *ctx = spi_controller_get_devdata(ctlr);
 
@@ -471,8 +397,7 @@ static int fsi_spi_transfer_one_message(struct spi_controller *ctlr,
                struct spi_transfer *next = NULL;
 
                /* Sequencer must do shift out (tx) first. */
-               if (!transfer->tx_buf ||
-                   transfer->len > (ctx->max_xfr_size + 8)) {
+               if (!transfer->tx_buf || transfer->len > SPI_FSI_MAX_TX_SIZE) {
                        rc = -EINVAL;
                        goto error;
                }
@@ -486,9 +411,13 @@ static int fsi_spi_transfer_one_message(struct spi_controller *ctlr,
                fsi_spi_sequence_init(&seq);
                fsi_spi_sequence_add(&seq, seq_slave);
 
-               rc = fsi_spi_sequence_transfer(ctx, &seq, transfer);
-               if (rc)
-                       goto error;
+               len = transfer->len;
+               while (len > 8) {
+                       fsi_spi_sequence_add(&seq,
+                                            SPI_FSI_SEQUENCE_SHIFT_OUT(8));
+                       len -= 8;
+               }
+               fsi_spi_sequence_add(&seq, SPI_FSI_SEQUENCE_SHIFT_OUT(len));
 
                if (!list_is_last(&transfer->transfer_list,
                                  &mesg->transfers)) {
@@ -496,7 +425,9 @@ static int fsi_spi_transfer_one_message(struct spi_controller *ctlr,
 
                        /* Sequencer can only do shift in (rx) after tx. */
                        if (next->rx_buf) {
-                               if (next->len > ctx->max_xfr_size) {
+                               u8 shift;
+
+                               if (next->len > SPI_FSI_MAX_RX_SIZE) {
                                        rc = -EINVAL;
                                        goto error;
                                }
@@ -504,10 +435,8 @@ static int fsi_spi_transfer_one_message(struct spi_controller *ctlr,
                                dev_dbg(ctx->dev, "Sequence rx of %d bytes.\n",
                                        next->len);
 
-                               rc = fsi_spi_sequence_transfer(ctx, &seq,
-                                                              next);
-                               if (rc)
-                                       goto error;
+                               shift = SPI_FSI_SEQUENCE_SHIFT_IN(next->len);
+                               fsi_spi_sequence_add(&seq, shift);
                        } else {
                                next = NULL;
                        }
@@ -541,9 +470,7 @@ error:
 
 static size_t fsi_spi_max_transfer_size(struct spi_device *spi)
 {
-       struct fsi_spi *ctx = spi_controller_get_devdata(spi->controller);
-
-       return ctx->max_xfr_size;
+       return SPI_FSI_MAX_RX_SIZE;
 }
 
 static int fsi_spi_probe(struct device *dev)
@@ -582,14 +509,6 @@ static int fsi_spi_probe(struct device *dev)
                ctx->fsi = fsi;
                ctx->base = base + SPI_FSI_BASE;
 
-               if (of_device_is_compatible(np, "ibm,fsi2spi-restricted")) {
-                       ctx->restricted = true;
-                       ctx->max_xfr_size = SPI_FSI_MAX_XFR_SIZE_RESTRICTED;
-               } else {
-                       ctx->restricted = false;
-                       ctx->max_xfr_size = SPI_FSI_MAX_XFR_SIZE;
-               }
-
                rc = devm_spi_register_controller(dev, ctlr);
                if (rc)
                        spi_controller_put(ctlr);