spi: fsl-espi: pre-allocate message buffer
Currently the driver allocates a 64kb buffer for each single message.
On systems with little and fragmented memory this can result in
memory allocation errors. Solve this by pre-allocating a buffer.
This patch was developed in OpenWRT long ago, however it never
made it upstream.
I slightly modified the original patch to re-initialize the buffer
at the beginning of each transfer.
Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/drivers/spi/spi-fsl-espi.c b/drivers/spi/spi-fsl-espi.c
index 16fff72..81d7416 100644
--- a/drivers/spi/spi-fsl-espi.c
+++ b/drivers/spi/spi-fsl-espi.c
@@ -297,57 +297,44 @@
static void fsl_espi_cmd_trans(struct spi_message *m,
struct fsl_espi_transfer *trans, u8 *rx_buff)
{
+ struct mpc8xxx_spi *mspi = spi_master_get_devdata(m->spi->master);
struct spi_transfer *t;
- u8 *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);
+ memcpy(mspi->local_buf + i, t->tx_buf, t->len);
i += t->len;
}
}
- espi_trans->tx_buf = local_buf;
- espi_trans->rx_buf = local_buf;
+ espi_trans->tx_buf = mspi->local_buf;
+ espi_trans->rx_buf = mspi->local_buf;
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 mpc8xxx_spi *mspi = spi_master_get_devdata(m->spi->master);
struct spi_transfer *t;
- u8 *local_buf;
unsigned int tx_only = 0;
int i = 0;
- local_buf = kzalloc(SPCOM_TRANLEN_MAX, GFP_KERNEL);
- if (!local_buf) {
- 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);
+ memcpy(mspi->local_buf + i, t->tx_buf, t->len);
i += t->len;
if (!t->rx_buf)
tx_only += t->len;
}
}
- trans->tx_buf = local_buf;
- trans->rx_buf = local_buf;
+ trans->tx_buf = mspi->local_buf;
+ trans->rx_buf = mspi->local_buf;
fsl_espi_do_trans(m, trans);
if (!trans->status) {
@@ -357,18 +344,19 @@
trans->len - tx_only);
trans->actual_length += trans->len;
}
-
- kfree(local_buf);
}
static int fsl_espi_do_one_msg(struct spi_master *master,
struct spi_message *m)
{
+ struct mpc8xxx_spi *mspi = spi_master_get_devdata(master);
struct spi_transfer *t;
u8 *rx_buf = NULL;
unsigned int xfer_len = 0;
struct fsl_espi_transfer espi_trans;
+ memset(mspi->local_buf, 0, SPCOM_TRANLEN_MAX);
+
list_for_each_entry(t, &m->transfers, transfer_list) {
if (t->rx_buf)
rx_buf = t->rx_buf;
@@ -614,6 +602,13 @@
mpc8xxx_spi = spi_master_get_devdata(master);
+ mpc8xxx_spi->local_buf =
+ devm_kmalloc(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);