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Diffstat (limited to 'target/linux/layerscape/patches-4.4/1107-mtd-fsl-quadspi-disable-AHB-buffer-prefetch.patch')
-rw-r--r--target/linux/layerscape/patches-4.4/1107-mtd-fsl-quadspi-disable-AHB-buffer-prefetch.patch67
1 files changed, 67 insertions, 0 deletions
diff --git a/target/linux/layerscape/patches-4.4/1107-mtd-fsl-quadspi-disable-AHB-buffer-prefetch.patch b/target/linux/layerscape/patches-4.4/1107-mtd-fsl-quadspi-disable-AHB-buffer-prefetch.patch
new file mode 100644
index 0000000000..19dff6c92e
--- /dev/null
+++ b/target/linux/layerscape/patches-4.4/1107-mtd-fsl-quadspi-disable-AHB-buffer-prefetch.patch
@@ -0,0 +1,67 @@
+From 50aac689d5be0a086f076cd4bc8b14ee0b9ab995 Mon Sep 17 00:00:00 2001
+From: Yunhui Cui <yunhui.cui@nxp.com>
+Date: Tue, 8 Mar 2016 14:38:52 +0800
+Subject: [PATCH 107/113] mtd: fsl-quadspi: disable AHB buffer prefetch
+
+A-009282: QuadSPI: QuadSPI data pre-fetch can result in incorrect data
+Affects: QuadSPI
+Description: With AHB buffer prefetch enabled, the QuadSPI may return
+incorrect data on the AHB
+interface. The buffer pre-fetch is enabled if the fetch size as
+configured either in the LUT or in
+the BUFxCR register is greater than 8 bytes.
+Impact: Only 64 bit read allowed.
+Workaround: Keep the read data size to 64 bits (8 Bytes), which disables
+the prefetch on the AHB buffer,
+and prevents this issue from occurring.
+
+Signed-off-by: Yunhui Cui <yunhui.cui@nxp.com>
+---
+ drivers/mtd/spi-nor/fsl-quadspi.c | 29 +++++++++++++++++++++++------
+ 1 file changed, 23 insertions(+), 6 deletions(-)
+
+--- a/drivers/mtd/spi-nor/fsl-quadspi.c
++++ b/drivers/mtd/spi-nor/fsl-quadspi.c
+@@ -794,19 +794,36 @@ static void fsl_qspi_init_abh_read(struc
+ {
+ void __iomem *base = q->iobase;
+ int seqid;
++ const struct fsl_qspi_devtype_data *devtype_data = q->devtype_data;
+
+ /* AHB configuration for access buffer 0/1/2 .*/
+ qspi_writel(q, QUADSPI_BUFXCR_INVALID_MSTRID, base + QUADSPI_BUF0CR);
+ qspi_writel(q, QUADSPI_BUFXCR_INVALID_MSTRID, base + QUADSPI_BUF1CR);
+ qspi_writel(q, QUADSPI_BUFXCR_INVALID_MSTRID, base + QUADSPI_BUF2CR);
++
+ /*
+- * Set ADATSZ with the maximum AHB buffer size to improve the
+- * read performance.
++ * Errata: A-009282: QuadSPI data prefetch may result in incorrect data
++ * Workaround: Keep the read data size to 64 bits (8 bytes).
++ * This disables the prefetch on the AHB buffer and
++ * prevents this issue from occurring.
+ */
+- qspi_writel(q, QUADSPI_BUF3CR_ALLMST_MASK |
+- ((q->devtype_data->ahb_buf_size / 8)
+- << QUADSPI_BUF3CR_ADATSZ_SHIFT),
+- base + QUADSPI_BUF3CR);
++ if (devtype_data->devtype == FSL_QUADSPI_LS2080A ||
++ devtype_data->devtype == FSL_QUADSPI_LS1021A) {
++
++ qspi_writel(q, QUADSPI_BUF3CR_ALLMST_MASK |
++ (1 << QUADSPI_BUF3CR_ADATSZ_SHIFT),
++ base + QUADSPI_BUF3CR);
++
++ } else {
++ /*
++ * Set ADATSZ with the maximum AHB buffer size to improve the
++ * read performance.
++ */
++ qspi_writel(q, QUADSPI_BUF3CR_ALLMST_MASK |
++ ((q->devtype_data->ahb_buf_size / 8)
++ << QUADSPI_BUF3CR_ADATSZ_SHIFT),
++ base + QUADSPI_BUF3CR);
++ }
+
+ /* We only use the buffer3 */
+ qspi_writel(q, 0, base + QUADSPI_BUF0IND);