spi: cadence_qspi_apb: Use 32 bit indirect write transaction when possible

[people/ms/u-boot.git] / drivers / spi / cadence_qspi_apb.c

diff --git a/drivers/spi/cadence_qspi_apb.c b/drivers/spi/cadence_qspi_apb.c
index df6a91fc9f7b66788b565ae60def4cd940479fdb..5d5b6f0d350b6cc58dd196dd0ed9ff361ce7fd6e 100644 (file)
--- a/drivers/spi/cadence_qspi_apb.c
+++ b/drivers/spi/cadence_qspi_apb.c
@@ -30,6 +30,7 @@
 #include <linux/errno.h>
 #include <wait_bit.h>
 #include <spi.h>
+#include <bouncebuf.h>
 #include "cadence_qspi.h"
 
 #define CQSPI_REG_POLL_US                      1 /* 1us */
@@ -724,6 +725,17 @@ int cadence_qspi_apb_indirect_write_execute(struct cadence_spi_platdata *plat,
        unsigned int remaining = n_tx;
        unsigned int write_bytes;
        int ret;
+       struct bounce_buffer bb;
+       u8 *bb_txbuf;
+
+       /*
+        * Handle non-4-byte aligned accesses via bounce buffer to
+        * avoid data abort.
+        */
+       ret = bounce_buffer_start(&bb, (void *)txbuf, n_tx, GEN_BB_READ);
+       if (ret)
+               return ret;
+       bb_txbuf = bb.bounce_buffer;
 
        /* Configure the indirect read transfer bytes */
        writel(n_tx, plat->regbase + CQSPI_REG_INDIRECTWRBYTES);
@@ -734,11 +746,11 @@ int cadence_qspi_apb_indirect_write_execute(struct cadence_spi_platdata *plat,
 
        while (remaining > 0) {
                write_bytes = remaining > page_size ? page_size : remaining;
-               /* Handle non-4-byte aligned access to avoid data abort. */
-               if (((uintptr_t)txbuf % 4) || (write_bytes % 4))
-                       writesb(plat->ahbbase, txbuf, write_bytes);
-               else
-                       writesl(plat->ahbbase, txbuf, write_bytes >> 2);
+               writesl(plat->ahbbase, bb_txbuf, write_bytes >> 2);
+               if (write_bytes % 4)
+                       writesb(plat->ahbbase,
+                               bb_txbuf + rounddown(write_bytes, 4),
+                               write_bytes % 4);
 
                ret = wait_for_bit("QSPI", plat->regbase + CQSPI_REG_SDRAMLEVEL,
                                   CQSPI_REG_SDRAMLEVEL_WR_MASK <<
@@ -748,7 +760,7 @@ int cadence_qspi_apb_indirect_write_execute(struct cadence_spi_platdata *plat,
                        goto failwr;
                }
 
-               txbuf += write_bytes;
+               bb_txbuf += write_bytes;
                remaining -= write_bytes;
        }
 
@@ -759,6 +771,7 @@ int cadence_qspi_apb_indirect_write_execute(struct cadence_spi_platdata *plat,
                printf("Indirect write completion error (%i)\n", ret);
                goto failwr;
        }
+       bounce_buffer_stop(&bb);
 
        /* Clear indirect completion status */
        writel(CQSPI_REG_INDIRECTWR_DONE,
@@ -769,6 +782,7 @@ failwr:
        /* Cancel the indirect write */
        writel(CQSPI_REG_INDIRECTWR_CANCEL,
               plat->regbase + CQSPI_REG_INDIRECTWR);
+       bounce_buffer_stop(&bb);
        return ret;
 }