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

This reverts commit 57897c13de.

Using bounce_buf.c to handle non-DMA alignment problems is bad as
bounce_buf.c does cache manipulations which is not required. Therefore
revert this patch in favour of local bounce buffer solution in the next
patch.

Signed-off-by: Vignesh R <vigneshr@ti.com>
Acked-by: Marek Vasut <marex@denx.de>
Acked-by: Simon Goldschmidt <sgoldschmidt@de.pepperl-fuchs.com>
Reviewed-by: Jason Rush <jarush@gmail.com>
Acked-by: Jason Rush <jarush@gmail.com>
Reviewed-by: Jagan Teki <jagan@openedev.com>

drivers/spi/cadence_qspi_apb.c

@@ -30,7 +30,6 @@
 #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 */
@@ -722,17 +721,6 @@ 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);
@@ -743,11 +731,11 @@ int cadence_qspi_apb_indirect_write_execute(struct cadence_spi_platdata *plat,
 
 	while (remaining > 0) {
 		write_bytes = remaining > page_size ? page_size : remaining;
-		writesl(plat->ahbbase, bb_txbuf, write_bytes >> 2);
-		if (write_bytes % 4)
-			writesb(plat->ahbbase,
-				bb_txbuf + rounddown(write_bytes, 4),
-				write_bytes % 4);
+		/* 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);
 
 		ret = wait_for_bit_le32(plat->regbase + CQSPI_REG_SDRAMLEVEL,
 					CQSPI_REG_SDRAMLEVEL_WR_MASK <<
@@ -757,7 +745,7 @@ int cadence_qspi_apb_indirect_write_execute(struct cadence_spi_platdata *plat,
 			goto failwr;
 		}
 
-		bb_txbuf += write_bytes;
+		txbuf += write_bytes;
 		remaining -= write_bytes;
 	}
 
@@ -768,7 +756,6 @@ 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,
@@ -779,7 +766,6 @@ failwr:
 	/* Cancel the indirect write */
 	writel(CQSPI_REG_INDIRECTWR_CANCEL,
 	       plat->regbase + CQSPI_REG_INDIRECTWR);
-	bounce_buffer_stop(&bb);
 	return ret;
 }
 

include/configs/k2g_evm.h

@@ -93,7 +93,6 @@
 #ifndef CONFIG_SPL_BUILD
 #define CONFIG_CADENCE_QSPI
 #define CONFIG_CQSPI_REF_CLK 384000000
-#define CONFIG_BOUNCE_BUFFER
 #endif
 
 #define SPI_MTD_PARTS	KEYSTONE_SPI1_MTD_PARTS

include/configs/socfpga_common.h

@@ -184,7 +184,6 @@ unsigned int cm_get_l4_sp_clk_hz(void);
 unsigned int cm_get_qspi_controller_clk_hz(void);
 #define CONFIG_CQSPI_REF_CLK		cm_get_qspi_controller_clk_hz()
 #endif
-#define CONFIG_BOUNCE_BUFFER
 
 /*
  * Designware SPI support

include/configs/stv0991.h

@@ -64,7 +64,6 @@
 + */
 #ifdef CONFIG_OF_CONTROL		/* QSPI is controlled via DT */
 #define CONFIG_CQSPI_REF_CLK		((30/4)/2)*1000*1000
-#define CONFIG_BOUNCE_BUFFER
 
 #endif