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Diffstat (limited to 'queue-6.12/spi-spi-mem-extend-spi-mem-operations-with-a-per-ope.patch')
-rw-r--r--queue-6.12/spi-spi-mem-extend-spi-mem-operations-with-a-per-ope.patch220
1 files changed, 0 insertions, 220 deletions
diff --git a/queue-6.12/spi-spi-mem-extend-spi-mem-operations-with-a-per-ope.patch b/queue-6.12/spi-spi-mem-extend-spi-mem-operations-with-a-per-ope.patch
deleted file mode 100644
index 5831735a27..0000000000
--- a/queue-6.12/spi-spi-mem-extend-spi-mem-operations-with-a-per-ope.patch
+++ /dev/null
@@ -1,220 +0,0 @@
-From 00311c92a5496aed8892149e05fc9b8d66c78b36 Mon Sep 17 00:00:00 2001
-From: Sasha Levin <sashal@kernel.org>
-Date: Tue, 24 Dec 2024 18:05:46 +0100
-Subject: spi: spi-mem: Extend spi-mem operations with a per-operation maximum
- frequency
-
-From: Miquel Raynal <miquel.raynal@bootlin.com>
-
-[ Upstream commit 0fefeade90e74bc8f40ab0e460f483565c492e28 ]
-
-In the spi subsystem, the bus frequency is derived as follows:
-- the controller may expose a minimum and maximum operating frequency
-- the hardware description, through the spi peripheral properties,
- advise what is the maximum acceptable frequency from a device/wiring
- point of view.
-Transfers must be observed at a frequency which fits both (so in
-practice, the lowest maximum).
-
-Actually, this second point mixes two information and already takes the
-lowest frequency among:
-- what the spi device is capable of (what is written in the component
- datasheet)
-- what the wiring allows (electromagnetic sensibility, crossovers,
- terminations, antenna effect, etc).
-
-This logic works until spi devices are no longer capable of sustaining
-their highest frequency regardless of the operation. Spi memories are
-typically subject to such variation. Some devices are capable of
-spitting their internally stored data (essentially in read mode) at a
-very fast rate, typically up to 166MHz on Winbond SPI-NAND chips, using
-"fast" commands. However, some of the low-end operations, such as
-regular page read-from-cache commands, are more limited and can only be
-executed at 54MHz at most. This is currently a problem in the SPI-NAND
-subsystem. Another situation, even if not yet supported, will be with
-DTR commands, when the data is latched on both edges of the clock. The
-same chips as mentioned previously are in this case limited to
-80MHz. Yet another example might be continuous reads, which, under
-certain circumstances, can also run at most at 104 or 120MHz.
-
-As a matter of fact, the "one frequency per chip" policy is outdated and
-more fine grain configuration is needed: we need to allow per-operation
-frequency limitations. So far, all datasheets I encountered advertise a
-maximum default frequency, which need to be lowered for certain specific
-operations. So based on the current infrastructure, we can still expect
-firmware (device trees in general) to continued advertising the same
-maximum speed which is a mix between the PCB limitations and the chip
-maximum capability, and expect per-operation lower frequencies when this
-is relevant.
-
-Add a `struct spi_mem_op` member to carry this information. Not
-providing this field explicitly from upper layers means that there is no
-further constraint and the default spi device maximum speed will be
-carried instead. The SPI_MEM_OP() macro is also expanded with an
-optional frequency argument, because virtually all operations can be
-subject to such a limitation, and this will allow for a smooth and
-discrete transition.
-
-For controller drivers which do not implement the spi-mem interface, the
-per-transfer speed is also set acordingly to a lower (than the maximum
-default) speed when relevant.
-
-Acked-by: Pratyush Yadav <pratyush@kernel.org>
-Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
-Link: https://patch.msgid.link/20241224-winbond-6-11-rc1-quad-support-v2-1-ad218dbc406f@bootlin.com
-Signed-off-by: Mark Brown <broonie@kernel.org>
-Signed-off-by: Sasha Levin <sashal@kernel.org>
----
- drivers/mtd/nand/spi/core.c | 2 ++
- drivers/spi/spi-mem.c | 28 ++++++++++++++++++++++++++++
- include/linux/spi/spi-mem.h | 12 +++++++++++-
- 3 files changed, 41 insertions(+), 1 deletion(-)
-
-diff --git a/drivers/mtd/nand/spi/core.c b/drivers/mtd/nand/spi/core.c
-index 4d76f9f71a0e9..075f513157603 100644
---- a/drivers/mtd/nand/spi/core.c
-+++ b/drivers/mtd/nand/spi/core.c
-@@ -1214,6 +1214,8 @@ spinand_select_op_variant(struct spinand_device *spinand,
- if (ret)
- break;
-
-+ spi_mem_adjust_op_freq(spinand->spimem, &op);
-+
- if (!spi_mem_supports_op(spinand->spimem, &op))
- break;
-
-diff --git a/drivers/spi/spi-mem.c b/drivers/spi/spi-mem.c
-index 17b8baf749e6a..f8b598ba962d9 100644
---- a/drivers/spi/spi-mem.c
-+++ b/drivers/spi/spi-mem.c
-@@ -184,6 +184,10 @@ bool spi_mem_default_supports_op(struct spi_mem *mem,
- return false;
- }
-
-+ if (op->max_freq && mem->spi->controller->min_speed_hz &&
-+ op->max_freq < mem->spi->controller->min_speed_hz)
-+ return false;
-+
- return spi_mem_check_buswidth(mem, op);
- }
- EXPORT_SYMBOL_GPL(spi_mem_default_supports_op);
-@@ -361,6 +365,9 @@ int spi_mem_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
- u8 *tmpbuf;
- int ret;
-
-+ /* Make sure the operation frequency is correct before going futher */
-+ spi_mem_adjust_op_freq(mem, (struct spi_mem_op *)op);
-+
- ret = spi_mem_check_op(op);
- if (ret)
- return ret;
-@@ -407,6 +414,7 @@ int spi_mem_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
- xfers[xferpos].tx_buf = tmpbuf;
- xfers[xferpos].len = op->cmd.nbytes;
- xfers[xferpos].tx_nbits = op->cmd.buswidth;
-+ xfers[xferpos].speed_hz = op->max_freq;
- spi_message_add_tail(&xfers[xferpos], &msg);
- xferpos++;
- totalxferlen++;
-@@ -421,6 +429,7 @@ int spi_mem_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
- xfers[xferpos].tx_buf = tmpbuf + 1;
- xfers[xferpos].len = op->addr.nbytes;
- xfers[xferpos].tx_nbits = op->addr.buswidth;
-+ xfers[xferpos].speed_hz = op->max_freq;
- spi_message_add_tail(&xfers[xferpos], &msg);
- xferpos++;
- totalxferlen += op->addr.nbytes;
-@@ -432,6 +441,7 @@ int spi_mem_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
- xfers[xferpos].len = op->dummy.nbytes;
- xfers[xferpos].tx_nbits = op->dummy.buswidth;
- xfers[xferpos].dummy_data = 1;
-+ xfers[xferpos].speed_hz = op->max_freq;
- spi_message_add_tail(&xfers[xferpos], &msg);
- xferpos++;
- totalxferlen += op->dummy.nbytes;
-@@ -447,6 +457,7 @@ int spi_mem_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
- }
-
- xfers[xferpos].len = op->data.nbytes;
-+ xfers[xferpos].speed_hz = op->max_freq;
- spi_message_add_tail(&xfers[xferpos], &msg);
- xferpos++;
- totalxferlen += op->data.nbytes;
-@@ -525,6 +536,23 @@ int spi_mem_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op)
- }
- EXPORT_SYMBOL_GPL(spi_mem_adjust_op_size);
-
-+/**
-+ * spi_mem_adjust_op_freq() - Adjust the frequency of a SPI mem operation to
-+ * match controller, PCB and chip limitations
-+ * @mem: the SPI memory
-+ * @op: the operation to adjust
-+ *
-+ * Some chips have per-op frequency limitations and must adapt the maximum
-+ * speed. This function allows SPI mem drivers to set @op->max_freq to the
-+ * maximum supported value.
-+ */
-+void spi_mem_adjust_op_freq(struct spi_mem *mem, struct spi_mem_op *op)
-+{
-+ if (!op->max_freq || op->max_freq > mem->spi->max_speed_hz)
-+ op->max_freq = mem->spi->max_speed_hz;
-+}
-+EXPORT_SYMBOL_GPL(spi_mem_adjust_op_freq);
-+
- static ssize_t spi_mem_no_dirmap_read(struct spi_mem_dirmap_desc *desc,
- u64 offs, size_t len, void *buf)
- {
-diff --git a/include/linux/spi/spi-mem.h b/include/linux/spi/spi-mem.h
-index f866d5c8ed32a..44b7ecee0e74c 100644
---- a/include/linux/spi/spi-mem.h
-+++ b/include/linux/spi/spi-mem.h
-@@ -68,6 +68,9 @@ enum spi_mem_data_dir {
- SPI_MEM_DATA_OUT,
- };
-
-+#define SPI_MEM_OP_MAX_FREQ(__freq) \
-+ .max_freq = __freq
-+
- /**
- * struct spi_mem_op - describes a SPI memory operation
- * @cmd.nbytes: number of opcode bytes (only 1 or 2 are valid). The opcode is
-@@ -95,6 +98,9 @@ enum spi_mem_data_dir {
- * operation does not involve transferring data
- * @data.buf.in: input buffer (must be DMA-able)
- * @data.buf.out: output buffer (must be DMA-able)
-+ * @max_freq: frequency limitation wrt this operation. 0 means there is no
-+ * specific constraint and the highest achievable frequency can be
-+ * attempted.
- */
- struct spi_mem_op {
- struct {
-@@ -132,14 +138,17 @@ struct spi_mem_op {
- const void *out;
- } buf;
- } data;
-+
-+ unsigned int max_freq;
- };
-
--#define SPI_MEM_OP(__cmd, __addr, __dummy, __data) \
-+#define SPI_MEM_OP(__cmd, __addr, __dummy, __data, ...) \
- { \
- .cmd = __cmd, \
- .addr = __addr, \
- .dummy = __dummy, \
- .data = __data, \
-+ __VA_ARGS__ \
- }
-
- /**
-@@ -365,6 +374,7 @@ bool spi_mem_default_supports_op(struct spi_mem *mem,
- #endif /* CONFIG_SPI_MEM */
-
- int spi_mem_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op);
-+void spi_mem_adjust_op_freq(struct spi_mem *mem, struct spi_mem_op *op);
-
- bool spi_mem_supports_op(struct spi_mem *mem,
- const struct spi_mem_op *op);
---
-2.39.5
-
generated by cgit 1.2.3-korg (git 2.43.0) at 2025-07-04 18:27:58 +0000