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-rw-r--r--target/linux/mpc85xx/patches-4.4/200-spi-fsl-espi-preallocate-local-buffer.patch127
1 files changed, 127 insertions, 0 deletions
diff --git a/target/linux/mpc85xx/patches-4.4/200-spi-fsl-espi-preallocate-local-buffer.patch b/target/linux/mpc85xx/patches-4.4/200-spi-fsl-espi-preallocate-local-buffer.patch
new file mode 100644
index 0000000000..3239cdb850
--- /dev/null
+++ b/target/linux/mpc85xx/patches-4.4/200-spi-fsl-espi-preallocate-local-buffer.patch
@@ -0,0 +1,127 @@
+From: Gabor Juhos <juhosg@openwrt.org>
+Subject: spi-fsl-espi: avoid frequent high order allocations
+
+The driver allocates 64KiB of memory fro a local buffer before
+each transfer and releases that afterwards. When the memory is
+fragmented this allocation often fails and causes a warning like
+this:
+
+ kworker/u2:2: page allocation failure: order:4, mode:0x10c0d0
+ CPU: 0 PID: 7011 Comm: kworker/u2:2 Not tainted 3.10.24 #1
+ Workqueue: ffe07000.spi mpc8xxx_spi_work
+ Call Trace:
+ [c1c6dcf0] [c0006914] show_stack+0x50/0x170 (unreliable)
+ [c1c6dd30] [c0259858] dump_stack+0x24/0x34
+ [c1c6dd40] [c00672e8] warn_alloc_failed+0x120/0x13c
+ [c1c6dd90] [c0069920] __alloc_pages_nodemask+0x574/0x5c8
+ [c1c6de20] [c0069990] __get_free_pages+0x1c/0x4c
+ [c1c6de30] [c0185174] fsl_espi_do_one_msg+0x128/0x2a0
+ [c1c6de90] [c0184290] mpc8xxx_spi_work+0x50/0x7c
+ [c1c6dea0] [c0037af8] process_one_work+0x208/0x30c
+ [c1c6dec0] [c00387a0] worker_thread+0x20c/0x308
+ [c1c6def0] [c003de60] kthread+0xa4/0xa8
+ [c1c6df40] [c000c4bc] ret_from_kernel_thread+0x5c/0x64
+
+ m25p80 spi0.0: error -12 reading SR
+ end_request: I/O error, dev mtdblock3, sector 680
+ SQUASHFS error: squashfs_read_data failed to read block 0x54a4a
+ SQUASHFS error: Unable to read data cache entry [54a4a]
+
+Preallocate the buffer from the probe routine to avoid
+this.
+
+Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
+Signed-off-by: Felix Fietkau <nbd@openwrt.org>
+---
+ drivers/spi/spi-fsl-espi.c | 34 ++++++++++++++++------------------
+ drivers/spi/spi-fsl-lib.h | 1 +
+ 2 files changed, 17 insertions(+), 18 deletions(-)
+
+--- a/drivers/spi/spi-fsl-espi.c
++++ b/drivers/spi/spi-fsl-espi.c
+@@ -332,17 +332,13 @@ static void fsl_espi_do_trans(struct spi
+ static void fsl_espi_cmd_trans(struct spi_message *m,
+ struct fsl_espi_transfer *trans, u8 *rx_buff)
+ {
++ struct spi_device *spi = m->spi;
++ struct mpc8xxx_spi *mspi = spi_master_get_devdata(spi->master);
+ struct spi_transfer *t;
+- u8 *local_buf;
++ u8 *local_buf = mspi->local_buf;
+ int i = 0;
+ struct fsl_espi_transfer *espi_trans = trans;
+
+- local_buf = kzalloc(SPCOM_TRANLEN_MAX, GFP_KERNEL);
+- if (!local_buf) {
+- espi_trans->status = -ENOMEM;
+- return;
+- }
+-
+ list_for_each_entry(t, &m->transfers, transfer_list) {
+ if (t->tx_buf) {
+ memcpy(local_buf + i, t->tx_buf, t->len);
+@@ -355,16 +351,17 @@ static void fsl_espi_cmd_trans(struct sp
+ fsl_espi_do_trans(m, espi_trans);
+
+ espi_trans->actual_length = espi_trans->len;
+- kfree(local_buf);
+ }
+
+ static void fsl_espi_rw_trans(struct spi_message *m,
+ struct fsl_espi_transfer *trans, u8 *rx_buff)
+ {
++ struct spi_device *spi = m->spi;
++ struct mpc8xxx_spi *mspi = spi_master_get_devdata(spi->master);
+ struct fsl_espi_transfer *espi_trans = trans;
+ unsigned int total_len = espi_trans->len;
+ struct spi_transfer *t;
+- u8 *local_buf;
++ u8 *local_buf = mspi->local_buf;
+ u8 *rx_buf = rx_buff;
+ unsigned int trans_len;
+ unsigned int addr;
+@@ -373,12 +370,6 @@ static void fsl_espi_rw_trans(struct spi
+ unsigned int pos;
+ int i, loop;
+
+- local_buf = kzalloc(SPCOM_TRANLEN_MAX, GFP_KERNEL);
+- if (!local_buf) {
+- espi_trans->status = -ENOMEM;
+- return;
+- }
+-
+ for (pos = 0, loop = 0; pos < total_len; pos += trans_len, loop++) {
+ trans_len = total_len - pos;
+
+@@ -424,8 +415,6 @@ static void fsl_espi_rw_trans(struct spi
+ else
+ espi_trans->actual_length += espi_trans->len;
+ }
+-
+- kfree(local_buf);
+ }
+
+ static int fsl_espi_do_one_msg(struct spi_master *master,
+@@ -673,6 +662,12 @@ static struct spi_master * fsl_espi_prob
+
+ mpc8xxx_spi = spi_master_get_devdata(master);
+
++ mpc8xxx_spi->local_buf = devm_kzalloc(dev, SPCOM_TRANLEN_MAX, GFP_KERNEL);
++ if (!mpc8xxx_spi->local_buf) {
++ ret = -ENOMEM;
++ goto err_probe;
++ }
++
+ mpc8xxx_spi->reg_base = devm_ioremap_resource(dev, mem);
+ if (IS_ERR(mpc8xxx_spi->reg_base)) {
+ ret = PTR_ERR(mpc8xxx_spi->reg_base);
+--- a/drivers/spi/spi-fsl-lib.h
++++ b/drivers/spi/spi-fsl-lib.h
+@@ -30,6 +30,7 @@ struct mpc8xxx_spi {
+ void *rx;
+ #if IS_ENABLED(CONFIG_SPI_FSL_ESPI)
+ int len;
++ u8 *local_buf;
+ #endif
+
+ int subblock;