spi: zynqmp_gqspi: Add parallel memories support in GQSPI driver

Add support for parallel memories in zynqmp_gqspi.c driver. In case of
parallel memories STRIPE bit is set and sent to the qspi ip, which will
send data bits to both the flashes in parallel. However for few commands
we should not use stripe, instead send same data to both the flashes.
Those commands are exclueded by using zynqmp_qspi_update_stripe().

Also update copyright info for this file.

Signed-off-by: Ashok Reddy Soma <ashok.reddy.soma@amd.com>
Signed-off-by: Venkatesh Yadav Abbarapu <venkatesh.abbarapu@amd.com>

diff --git a/drivers/spi/zynqmp_gqspi.c b/drivers/spi/zynqmp_gqspi.c
index ae795e50b0a53efb4173d007efabb42ad6cb22bd..1d19b2606c50c2bf824991f32b111009e410dad8 100644 (file)
--- a/drivers/spi/zynqmp_gqspi.c
+++ b/drivers/spi/zynqmp_gqspi.c
@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * (C) Copyright 2018 Xilinx
- *
+ * (C) Copyright 2013 - 2022, Xilinx, Inc.
+ * (C) Copyright 2023, Advanced Micro Devices, Inc.
  * Xilinx ZynqMP Generic Quad-SPI(QSPI) controller driver(master mode only)
  */
 
@@ -24,6 +24,8 @@
 #include <linux/bitops.h>
 #include <linux/err.h>
 #include <linux/sizes.h>
+#include <linux/mtd/spi-nor.h>
+#include "../mtd/spi/sf_internal.h"
 #include <zynqmp_firmware.h>
 
 #define GQSPI_GFIFO_STRT_MODE_MASK     BIT(29)
@@ -87,6 +89,9 @@
 #define SPI_XFER_ON_LOWER              1
 #define SPI_XFER_ON_UPPER              2
 
+#define GQSPI_SELECT_LOWER_CS          BIT(0)
+#define GQSPI_SELECT_UPPER_CS          BIT(1)
+
 #define GQSPI_DMA_ALIGN                        0x4
 #define GQSPI_MAX_BAUD_RATE_VAL                7
 #define GQSPI_DFLT_BAUD_RATE_VAL       2
@@ -183,13 +188,14 @@ struct zynqmp_qspi_priv {
        int bytes_to_transfer;
        int bytes_to_receive;
        const struct spi_mem_op *op;
+       unsigned int is_parallel;
+       unsigned int u_page;
+       unsigned int bus;
+       unsigned int stripe;
+       unsigned int flags;
+       u32 max_hz;
 };
 
-__weak int zynqmp_mmio_write(const u32 address, const u32 mask, const u32 value)
-{
-       return 0;
-}
-
 static int zynqmp_qspi_of_to_plat(struct udevice *bus)
 {
        struct zynqmp_qspi_plat *plat = dev_get_plat(bus);
@@ -234,8 +240,30 @@ static u32 zynqmp_qspi_bus_select(struct zynqmp_qspi_priv *priv)
 {
        u32 gqspi_fifo_reg = 0;
 
-       gqspi_fifo_reg = GQSPI_GFIFO_LOW_BUS |
-                        GQSPI_GFIFO_CS_LOWER;
+       if (priv->is_parallel) {
+               if (priv->bus == SPI_XFER_ON_BOTH)
+                       gqspi_fifo_reg = GQSPI_GFIFO_LOW_BUS |
+                                        GQSPI_GFIFO_UP_BUS |
+                                        GQSPI_GFIFO_CS_UPPER |
+                                        GQSPI_GFIFO_CS_LOWER;
+               else if (priv->bus == SPI_XFER_ON_LOWER)
+                       gqspi_fifo_reg = GQSPI_GFIFO_LOW_BUS |
+                                        GQSPI_GFIFO_CS_UPPER |
+                                        GQSPI_GFIFO_CS_LOWER;
+               else if (priv->bus == SPI_XFER_ON_UPPER)
+                       gqspi_fifo_reg = GQSPI_GFIFO_UP_BUS |
+                                        GQSPI_GFIFO_CS_LOWER |
+                                        GQSPI_GFIFO_CS_UPPER;
+               else
+                       debug("Wrong Bus selection:0x%x\n", priv->bus);
+       } else {
+               if (priv->u_page)
+                       gqspi_fifo_reg = GQSPI_GFIFO_LOW_BUS |
+                                        GQSPI_GFIFO_CS_UPPER;
+               else
+                       gqspi_fifo_reg = GQSPI_GFIFO_LOW_BUS |
+                                        GQSPI_GFIFO_CS_LOWER;
+       }
 
        return gqspi_fifo_reg;
 }
@@ -295,8 +323,15 @@ static void zynqmp_qspi_chipselect(struct zynqmp_qspi_priv *priv, int is_on)
                gqspi_fifo_reg |= GQSPI_SPI_MODE_SPI |
                                  GQSPI_IMD_DATA_CS_ASSERT;
        } else {
-               gqspi_fifo_reg = GQSPI_GFIFO_LOW_BUS;
-               gqspi_fifo_reg |= GQSPI_IMD_DATA_CS_DEASSERT;
+               if (priv->is_parallel) {
+                       gqspi_fifo_reg = GQSPI_GFIFO_UP_BUS |
+                                        GQSPI_GFIFO_LOW_BUS;
+               } else if (priv->u_page) {
+                       gqspi_fifo_reg = GQSPI_GFIFO_UP_BUS;
+               } else {
+                       gqspi_fifo_reg = GQSPI_GFIFO_LOW_BUS;
+                       gqspi_fifo_reg |= GQSPI_IMD_DATA_CS_DEASSERT;
+               }
        }
 
        zynqmp_qspi_fill_gen_fifo(priv, gqspi_fifo_reg);
@@ -367,12 +402,13 @@ static int zynqmp_qspi_set_speed(struct udevice *bus, uint speed)
 
        log_debug("%s, Speed: %d, Max: %d\n", __func__, speed, plat->frequency);
 
-       if (speed > plat->frequency)
-               speed = plat->frequency;
+       /*
+        * If speed == 0 or speed > max freq, then set speed to highest
+        */
+       if (!speed || speed > priv->max_hz)
+               speed = priv->max_hz;
 
        if (plat->speed_hz != speed) {
-               /* Set the clock frequency */
-               /* If speed == 0, default to lowest speed */
                while ((baud_rate_val < 8) &&
                       ((plat->frequency /
                       (2 << baud_rate_val)) > speed))
@@ -394,6 +430,18 @@ static int zynqmp_qspi_set_speed(struct udevice *bus, uint speed)
        return 0;
 }
 
+static int zynqmp_qspi_child_pre_probe(struct udevice *bus)
+{
+       struct spi_slave *slave = dev_get_parent_priv(bus);
+       struct zynqmp_qspi_priv *priv = dev_get_priv(bus->parent);
+
+       slave->multi_cs_cap = true;
+       slave->bytemode = SPI_4BYTE_MODE;
+       priv->max_hz = slave->max_hz;
+
+       return 0;
+}
+
 static int zynqmp_qspi_probe(struct udevice *bus)
 {
        struct zynqmp_qspi_plat *plat = dev_get_plat(bus);
@@ -458,12 +506,17 @@ static int zynqmp_qspi_set_mode(struct udevice *bus, uint mode)
 
 static int zynqmp_qspi_fill_tx_fifo(struct zynqmp_qspi_priv *priv, u32 size)
 {
-       u32 data;
+       u32 data, ier;
        int ret = 0;
        struct zynqmp_qspi_regs *regs = priv->regs;
        u32 *buf = (u32 *)priv->tx_buf;
        u32 len = size;
 
+       /* Enable interrupts */
+       ier = readl(&regs->ier);
+       ier |= GQSPI_IXR_ALL_MASK | GQSPI_IXR_TXFIFOEMPTY_MASK;
+       writel(ier, &regs->ier);
+
        while (size) {
                ret = wait_for_bit_le32(&regs->isr, GQSPI_IXR_TXNFULL_MASK, 1,
                                        GQSPI_TIMEOUT, 1);
@@ -586,6 +639,9 @@ static int zynqmp_qspi_genfifo_fill_tx(struct zynqmp_qspi_priv *priv)
        gen_fifo_cmd |= zynqmp_qspi_genfifo_mode(priv->op->data.buswidth);
        gen_fifo_cmd |= GQSPI_GFIFO_TX | GQSPI_GFIFO_DATA_XFR_MASK;
 
+       if (priv->stripe)
+               gen_fifo_cmd |= GQSPI_GFIFO_STRIPE_MASK;
+
        while (priv->len) {
                len = zynqmp_qspi_calc_exp(priv, &gen_fifo_cmd);
                zynqmp_qspi_fill_gen_fifo(priv, gen_fifo_cmd);
@@ -720,6 +776,9 @@ static int zynqmp_qspi_genfifo_fill_rx(struct zynqmp_qspi_priv *priv)
        gen_fifo_cmd |= zynqmp_qspi_genfifo_mode(priv->op->data.buswidth);
        gen_fifo_cmd |= GQSPI_GFIFO_RX | GQSPI_GFIFO_DATA_XFR_MASK;
 
+       if (priv->stripe)
+               gen_fifo_cmd |= GQSPI_GFIFO_STRIPE_MASK;
+
        /*
         * Check if receive buffer is aligned to 4 byte and length
         * is multiples of four byte as we are using dma to receive.
@@ -760,6 +819,33 @@ static int zynqmp_qspi_release_bus(struct udevice *dev)
        return 0;
 }
 
+static bool zynqmp_qspi_update_stripe(const struct spi_mem_op *op)
+{
+       /*
+        * This is a list of opcodes for which we must not use striped access
+        * even in dual parallel mode, but instead broadcast the same data to
+        * both chips. This is primarily erase commands and writing some
+        * registers.
+        */
+       switch (op->cmd.opcode) {
+       case SPINOR_OP_BE_4K:
+       case SPINOR_OP_BE_32K:
+       case SPINOR_OP_CHIP_ERASE:
+       case SPINOR_OP_SE:
+       case SPINOR_OP_BE_32K_4B:
+       case SPINOR_OP_SE_4B:
+       case SPINOR_OP_BE_4K_4B:
+       case SPINOR_OP_WRSR:
+       case SPINOR_OP_WREAR:
+       case SPINOR_OP_BRWR:
+               return false;
+       case SPINOR_OP_WRSR2:
+               return op->addr.nbytes != 0;
+       default:
+               return true;
+       }
+}
+
 static int zynqmp_qspi_exec_op(struct spi_slave *slave,
                               const struct spi_mem_op *op)
 {
@@ -771,6 +857,25 @@ static int zynqmp_qspi_exec_op(struct spi_slave *slave,
        priv->rx_buf = op->data.buf.in;
        priv->len = op->data.nbytes;
 
+       if (slave->flags & SPI_XFER_U_PAGE)
+               priv->u_page = 1;
+       else
+               priv->u_page = 0;
+
+       if ((slave->flags & GQSPI_SELECT_LOWER_CS) &&
+           (slave->flags & GQSPI_SELECT_UPPER_CS))
+               priv->is_parallel = true;
+
+       priv->stripe = 0;
+       priv->bus = 0;
+
+       if (priv->is_parallel) {
+               if (slave->flags & SPI_XFER_MASK)
+                       priv->bus = (slave->flags & SPI_XFER_MASK) >> 8;
+               if (zynqmp_qspi_update_stripe(op))
+                       priv->stripe = 1;
+       }
+
        zynqmp_qspi_chipselect(priv, 1);
 
        /* Send opcode, addr, dummy */
@@ -784,6 +889,9 @@ static int zynqmp_qspi_exec_op(struct spi_slave *slave,
 
        zynqmp_qspi_chipselect(priv, 0);
 
+       priv->is_parallel = false;
+       slave->flags &= ~SPI_XFER_MASK;
+
        return ret;
 }
 
@@ -814,4 +922,5 @@ U_BOOT_DRIVER(zynqmp_qspi) = {
        .plat_auto      = sizeof(struct zynqmp_qspi_plat),
        .priv_auto      = sizeof(struct zynqmp_qspi_priv),
        .probe  = zynqmp_qspi_probe,
+       .child_pre_probe = zynqmp_qspi_child_pre_probe,
 };

diff --git a/include/spi.h b/include/spi.h
index b7148864e78ffdb87cf2391ee3a46a56d5e2c560..3a92d02f21548590b7a1605e5ce729f2431c44e1 100644 (file)
--- a/include/spi.h
+++ b/include/spi.h
@@ -38,6 +38,9 @@
 
 #define SPI_DEFAULT_WORDLEN    8
 
+#define SPI_3BYTE_MODE 0x0
+#define SPI_4BYTE_MODE 0x1
+
 /* SPI transfer flags */
 #define SPI_XFER_STRIPE        (1 << 6)
 #define SPI_XFER_MASK  (3 << 8)
@@ -172,6 +175,7 @@ struct spi_slave {
         * at once.
         */
        bool multi_cs_cap;
+       u32 bytemode;
 };
 
 /**