* [PATCH v5 1/2] mtd: spi-nor: split spi_nor_spimem_xfer_data()
2020-02-18 21:16 [PATCH v5 0/2] mtd: spi-nor: use spi-mem dirmap API Sergei Shtylyov
@ 2020-02-18 21:21 ` Sergei Shtylyov
2020-02-18 21:24 ` [PATCH v5 2/2] mtd: spi-nor: use spi-mem dirmap API Sergei Shtylyov
2020-02-19 7:41 ` [PATCH v5 0/2] " Tudor.Ambarus
2 siblings, 0 replies; 4+ messages in thread
From: Sergei Shtylyov @ 2020-02-18 21:21 UTC (permalink / raw)
To: Tudor Ambarus, Miquel Raynal, Richard Weinberger,
Vignesh Raghavendra, linux-mtd
spi_nor_spimem_xfer_data() being a helper function for the data reads/
writes contains 3 fragments that depend on the data direction; and I'm
going to add another one to call the SPI dirmap API...
I think this function should be split so that the common fragments are
put into 2 functions, spi_nor_spimem_bounce() and spi_nor_spimem_exec_op()
called from spi_nor_spimem_{read|write}_data(), and the data direction
dependent bits moved back into those read/write functions -- that way we
would be able to avoid *goto*s otherwise needed in the next patch adding
the SPI dirmap support...
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
---
Changes in version 5:
- removed the 'usebouncebuf' local variable from spi_nor_spimem_write_data();
- refreshed the patch.
Changes in version 4:
- new patch.
drivers/mtd/spi-nor/spi-nor.c | 89 +++++++++++++++++++++++-------------------
1 file changed, 49 insertions(+), 40 deletions(-)
Index: linux/drivers/mtd/spi-nor/spi-nor.c
===================================================================
--- linux.orig/drivers/mtd/spi-nor/spi-nor.c
+++ linux/drivers/mtd/spi-nor/spi-nor.c
@@ -246,55 +246,45 @@ struct flash_info {
#define JEDEC_MFR(info) ((info)->id[0])
/**
- * spi_nor_spimem_xfer_data() - helper function to read/write data to
- * flash's memory region
+ * spi_nor_spimem_bounce() - check if a bounce buffer is needed for the data
+ * transfer
* @nor: pointer to 'struct spi_nor'
* @op: pointer to 'struct spi_mem_op' template for transfer
*
- * Return: number of bytes transferred on success, -errno otherwise
+ * If we have to use the bounce buffer, the data field in @op will be updated.
+ *
+ * Return: true if the bounce buffer is needed, false if not
*/
-static ssize_t spi_nor_spimem_xfer_data(struct spi_nor *nor,
- struct spi_mem_op *op)
+static bool spi_nor_spimem_bounce(struct spi_nor *nor, struct spi_mem_op *op)
{
- bool usebouncebuf = false;
- void *rdbuf = NULL;
- const void *buf;
- int ret;
-
- if (op->data.dir == SPI_MEM_DATA_IN)
- buf = op->data.buf.in;
- else
- buf = op->data.buf.out;
-
- if (object_is_on_stack(buf) || !virt_addr_valid(buf))
- usebouncebuf = true;
-
- if (usebouncebuf) {
+ /* op->data.buf.in occupies the same memory as op->data.buf.out */
+ if (object_is_on_stack(op->data.buf.in) ||
+ !virt_addr_valid(op->data.buf.in)) {
if (op->data.nbytes > nor->bouncebuf_size)
op->data.nbytes = nor->bouncebuf_size;
-
- if (op->data.dir == SPI_MEM_DATA_IN) {
- rdbuf = op->data.buf.in;
- op->data.buf.in = nor->bouncebuf;
- } else {
- op->data.buf.out = nor->bouncebuf;
- memcpy(nor->bouncebuf, buf,
- op->data.nbytes);
- }
+ op->data.buf.in = nor->bouncebuf;
+ return true;
}
- ret = spi_mem_adjust_op_size(nor->spimem, op);
- if (ret)
- return ret;
-
- ret = spi_mem_exec_op(nor->spimem, op);
- if (ret)
- return ret;
+ return false;
+}
- if (usebouncebuf && op->data.dir == SPI_MEM_DATA_IN)
- memcpy(rdbuf, nor->bouncebuf, op->data.nbytes);
+/**
+ * spi_nor_spimem_exec_op() - execute a memory operation
+ * @nor: pointer to 'struct spi_nor'
+ * @op: pointer to 'struct spi_mem_op' template for transfer
+ *
+ * Return: 0 on success, -error otherwise.
+ */
+static int spi_nor_spimem_exec_op(struct spi_nor *nor, struct spi_mem_op *op)
+{
+ int error;
- return op->data.nbytes;
+ error = spi_mem_adjust_op_size(nor->spimem, op);
+ if (error)
+ return error;
+
+ return spi_mem_exec_op(nor->spimem, op);
}
/**
@@ -315,6 +305,8 @@ static ssize_t spi_nor_spimem_read_data(
SPI_MEM_OP_ADDR(nor->addr_width, from, 1),
SPI_MEM_OP_DUMMY(nor->read_dummy, 1),
SPI_MEM_OP_DATA_IN(len, buf, 1));
+ bool usebouncebuf;
+ int error;
/* get transfer protocols. */
op.cmd.buswidth = spi_nor_get_protocol_inst_nbits(nor->read_proto);
@@ -325,7 +317,16 @@ static ssize_t spi_nor_spimem_read_data(
/* convert the dummy cycles to the number of bytes */
op.dummy.nbytes = (nor->read_dummy * op.dummy.buswidth) / 8;
- return spi_nor_spimem_xfer_data(nor, &op);
+ usebouncebuf = spi_nor_spimem_bounce(nor, &op);
+
+ error = spi_nor_spimem_exec_op(nor, &op);
+ if (error)
+ return error;
+
+ if (usebouncebuf)
+ memcpy(buf, op.data.buf.in, op.data.nbytes);
+
+ return op.data.nbytes;
}
/**
@@ -364,6 +365,7 @@ static ssize_t spi_nor_spimem_write_data
SPI_MEM_OP_ADDR(nor->addr_width, to, 1),
SPI_MEM_OP_NO_DUMMY,
SPI_MEM_OP_DATA_OUT(len, buf, 1));
+ int error;
op.cmd.buswidth = spi_nor_get_protocol_inst_nbits(nor->write_proto);
op.addr.buswidth = spi_nor_get_protocol_addr_nbits(nor->write_proto);
@@ -372,7 +374,14 @@ static ssize_t spi_nor_spimem_write_data
if (nor->program_opcode == SPINOR_OP_AAI_WP && nor->sst_write_second)
op.addr.nbytes = 0;
- return spi_nor_spimem_xfer_data(nor, &op);
+ if (spi_nor_spimem_bounce(nor, &op))
+ memcpy(nor->bouncebuf, buf, op.data.nbytes);
+
+ error = spi_nor_spimem_exec_op(nor, &op);
+ if (error)
+ return error;
+
+ return op.data.nbytes;
}
/**
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^ permalink raw reply [flat|nested] 4+ messages in thread* [PATCH v5 2/2] mtd: spi-nor: use spi-mem dirmap API
2020-02-18 21:16 [PATCH v5 0/2] mtd: spi-nor: use spi-mem dirmap API Sergei Shtylyov
2020-02-18 21:21 ` [PATCH v5 1/2] mtd: spi-nor: split spi_nor_spimem_xfer_data() Sergei Shtylyov
@ 2020-02-18 21:24 ` Sergei Shtylyov
2020-02-19 7:41 ` [PATCH v5 0/2] " Tudor.Ambarus
2 siblings, 0 replies; 4+ messages in thread
From: Sergei Shtylyov @ 2020-02-18 21:24 UTC (permalink / raw)
To: Tudor Ambarus, Miquel Raynal, Richard Weinberger,
Vignesh Raghavendra, linux-mtd
Make use of the spi-mem direct mapping API to let advanced controllers
optimize read/write operations when they support direct mapping.
Based on the original patch by Boris Brezillon
<boris.brezillon@bootlin.com>.
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
---
Changes in version 5:
- transformed *if*/return* statements into an extra check before the memcpy()
call and removed an empty line in spi_nor_spimem_read_data();
- resolved a reject when adding the 'nbytes' local variable and refreshed
atop of the previous patch in spi_nor_spimem_write_data();
- removed the unnecessary *if*/return* statements in
spi_nor_spimem_write_data();
- added the 'kernel-doc' comment for the 'dirmap' field of the 'struct spi_nor';
- refreshed the patch.
Changes in version 4:
- moved the spi_mem_dirmap_{read|write}() calls closer to the ending of
spi_nor_{read|write}(), adapting to the chnages caused by the new patch
splitting spi_nor_spimem_xfer_data()...
Changes in version 3:
- simplified the way spi_mem_dirmap_{read|write}() are called;
- added Boris' tag.
Changes in version 2:
- moved the spi_mem_dirmap_{read|write}() calls from spi_nor_{read|write}() to
spi_nor_spimem_{read|write}_data().
drivers/mtd/spi-nor/spi-nor.c | 94 +++++++++++++++++++++++++++++++++++++-----
include/linux/mtd/spi-nor.h | 6 ++
2 files changed, 90 insertions(+), 10 deletions(-)
Index: linux/drivers/mtd/spi-nor/spi-nor.c
===================================================================
--- linux.orig/drivers/mtd/spi-nor/spi-nor.c
+++ linux/drivers/mtd/spi-nor/spi-nor.c
@@ -306,6 +306,7 @@ static ssize_t spi_nor_spimem_read_data(
SPI_MEM_OP_DUMMY(nor->read_dummy, 1),
SPI_MEM_OP_DATA_IN(len, buf, 1));
bool usebouncebuf;
+ ssize_t nbytes;
int error;
/* get transfer protocols. */
@@ -319,14 +320,20 @@ static ssize_t spi_nor_spimem_read_data(
usebouncebuf = spi_nor_spimem_bounce(nor, &op);
- error = spi_nor_spimem_exec_op(nor, &op);
- if (error)
- return error;
+ if (nor->dirmap.rdesc) {
+ nbytes = spi_mem_dirmap_read(nor->dirmap.rdesc, op.addr.val,
+ op.data.nbytes, op.data.buf.in);
+ } else {
+ error = spi_nor_spimem_exec_op(nor, &op);
+ if (error)
+ return error;
+ nbytes = op.data.nbytes;
+ }
- if (usebouncebuf)
- memcpy(buf, op.data.buf.in, op.data.nbytes);
+ if (usebouncebuf && nbytes > 0)
+ memcpy(buf, op.data.buf.in, nbytes);
- return op.data.nbytes;
+ return nbytes;
}
/**
@@ -365,6 +372,7 @@ static ssize_t spi_nor_spimem_write_data
SPI_MEM_OP_ADDR(nor->addr_width, to, 1),
SPI_MEM_OP_NO_DUMMY,
SPI_MEM_OP_DATA_OUT(len, buf, 1));
+ ssize_t nbytes;
int error;
op.cmd.buswidth = spi_nor_get_protocol_inst_nbits(nor->write_proto);
@@ -377,11 +385,17 @@ static ssize_t spi_nor_spimem_write_data
if (spi_nor_spimem_bounce(nor, &op))
memcpy(nor->bouncebuf, buf, op.data.nbytes);
- error = spi_nor_spimem_exec_op(nor, &op);
- if (error)
- return error;
+ if (nor->dirmap.wdesc) {
+ nbytes = spi_mem_dirmap_write(nor->dirmap.wdesc, op.addr.val,
+ op.data.nbytes, op.data.buf.out);
+ } else {
+ error = spi_nor_spimem_exec_op(nor, &op);
+ if (error)
+ return error;
+ nbytes = op.data.nbytes;
+ }
- return op.data.nbytes;
+ return nbytes;
}
/**
@@ -5265,6 +5279,58 @@ int spi_nor_scan(struct spi_nor *nor, co
}
EXPORT_SYMBOL_GPL(spi_nor_scan);
+static int spi_nor_create_read_dirmap(struct spi_nor *nor)
+{
+ struct spi_mem_dirmap_info info = {
+ .op_tmpl = SPI_MEM_OP(SPI_MEM_OP_CMD(nor->read_opcode, 1),
+ SPI_MEM_OP_ADDR(nor->addr_width, 0, 1),
+ SPI_MEM_OP_DUMMY(nor->read_dummy, 1),
+ SPI_MEM_OP_DATA_IN(0, NULL, 1)),
+ .offset = 0,
+ .length = nor->mtd.size,
+ };
+ struct spi_mem_op *op = &info.op_tmpl;
+
+ /* get transfer protocols. */
+ op->cmd.buswidth = spi_nor_get_protocol_inst_nbits(nor->read_proto);
+ op->addr.buswidth = spi_nor_get_protocol_addr_nbits(nor->read_proto);
+ op->dummy.buswidth = op->addr.buswidth;
+ op->data.buswidth = spi_nor_get_protocol_data_nbits(nor->read_proto);
+
+ /* convert the dummy cycles to the number of bytes */
+ op->dummy.nbytes = (nor->read_dummy * op->dummy.buswidth) / 8;
+
+ nor->dirmap.rdesc = devm_spi_mem_dirmap_create(nor->dev, nor->spimem,
+ &info);
+ return PTR_ERR_OR_ZERO(nor->dirmap.rdesc);
+}
+
+static int spi_nor_create_write_dirmap(struct spi_nor *nor)
+{
+ struct spi_mem_dirmap_info info = {
+ .op_tmpl = SPI_MEM_OP(SPI_MEM_OP_CMD(nor->program_opcode, 1),
+ SPI_MEM_OP_ADDR(nor->addr_width, 0, 1),
+ SPI_MEM_OP_NO_DUMMY,
+ SPI_MEM_OP_DATA_OUT(0, NULL, 1)),
+ .offset = 0,
+ .length = nor->mtd.size,
+ };
+ struct spi_mem_op *op = &info.op_tmpl;
+
+ /* get transfer protocols. */
+ op->cmd.buswidth = spi_nor_get_protocol_inst_nbits(nor->write_proto);
+ op->addr.buswidth = spi_nor_get_protocol_addr_nbits(nor->write_proto);
+ op->dummy.buswidth = op->addr.buswidth;
+ op->data.buswidth = spi_nor_get_protocol_data_nbits(nor->write_proto);
+
+ if (nor->program_opcode == SPINOR_OP_AAI_WP && nor->sst_write_second)
+ op->addr.nbytes = 0;
+
+ nor->dirmap.wdesc = devm_spi_mem_dirmap_create(nor->dev, nor->spimem,
+ &info);
+ return PTR_ERR_OR_ZERO(nor->dirmap.wdesc);
+}
+
static int spi_nor_probe(struct spi_mem *spimem)
{
struct spi_device *spi = spimem->spi;
@@ -5326,6 +5392,14 @@ static int spi_nor_probe(struct spi_mem
return -ENOMEM;
}
+ ret = spi_nor_create_read_dirmap(nor);
+ if (ret)
+ return ret;
+
+ ret = spi_nor_create_write_dirmap(nor);
+ if (ret)
+ return ret;
+
return mtd_device_register(&nor->mtd, data ? data->parts : NULL,
data ? data->nr_parts : 0);
}
Index: linux/include/linux/mtd/spi-nor.h
===================================================================
--- linux.orig/include/linux/mtd/spi-nor.h
+++ linux/include/linux/mtd/spi-nor.h
@@ -580,6 +580,7 @@ struct flash_info;
* The structure includes legacy flash parameters and
* settings that can be overwritten by the spi_nor_fixups
* hooks, or dynamically when parsing the SFDP tables.
+ * @dirmap: pointers to struct spi_mem_dirmap_desc for reads/writes.
* @priv: the private data
*/
struct spi_nor {
@@ -606,6 +607,11 @@ struct spi_nor {
struct spi_nor_flash_parameter params;
+ struct {
+ struct spi_mem_dirmap_desc *rdesc;
+ struct spi_mem_dirmap_desc *wdesc;
+ } dirmap;
+
void *priv;
};
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^ permalink raw reply [flat|nested] 4+ messages in thread