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Unverified Commit c76f5089 authored by Boris Brezillon's avatar Boris Brezillon Committed by Tudor Ambarus
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mtd: spi-nor: Rework hwcaps selection for the spi-mem case 



The spi-mem layer provides a spi_mem_supports_op() function to check
whether a specific operation is supported by the controller or not.
This is much more accurate than the hwcaps selection logic based on
SPI_{RX,TX}_ flags.

Rework the hwcaps selection logic to use spi_mem_supports_op() when
nor->spimem != NULL.

Signed-off-by: default avatarBoris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: default avatarVignesh Raghavendra <vigneshr@ti.com>
Signed-off-by: default avatarTudor Ambarus <tudor.ambarus@microchip.com>
parent b35b9a10

drivers/mtd/spi-nor/spi-nor.c

+147 −36
Original line number Diff line number Diff line
@@ -2951,6 +2951,129 @@ static int spi_nor_read_sfdp(struct spi_nor *nor, u32 addr, 
	return ret;

}



/**

 * spi_nor_spimem_check_op - check if the operation is supported

 *                           by controller

 *@nor:        pointer to a 'struct spi_nor'

 *@op:         pointer to op template to be checked

 *

 * Returns 0 if operation is supported, -ENOTSUPP otherwise.

 */

static int spi_nor_spimem_check_op(struct spi_nor *nor,

				   struct spi_mem_op *op)

{

	/*

	 * First test with 4 address bytes. The opcode itself might

	 * be a 3B addressing opcode but we don't care, because

	 * SPI controller implementation should not check the opcode,

	 * but just the sequence.

	 */

	op->addr.nbytes = 4;

	if (!spi_mem_supports_op(nor->spimem, op)) {

		if (nor->mtd.size > SZ_16M)

			return -ENOTSUPP;



		/* If flash size <= 16MB, 3 address bytes are sufficient */

		op->addr.nbytes = 3;

		if (!spi_mem_supports_op(nor->spimem, op))

			return -ENOTSUPP;

	}



	return 0;

}



/**

 * spi_nor_spimem_check_readop - check if the read op is supported

 *                               by controller

 *@nor:         pointer to a 'struct spi_nor'

 *@read:        pointer to op template to be checked

 *

 * Returns 0 if operation is supported, -ENOTSUPP otherwise.

 */

static int spi_nor_spimem_check_readop(struct spi_nor *nor,

				       const struct spi_nor_read_command *read)

{

	struct spi_mem_op op = SPI_MEM_OP(SPI_MEM_OP_CMD(read->opcode, 1),

					  SPI_MEM_OP_ADDR(3, 0, 1),

					  SPI_MEM_OP_DUMMY(0, 1),

					  SPI_MEM_OP_DATA_IN(0, NULL, 1));



	op.cmd.buswidth = spi_nor_get_protocol_inst_nbits(read->proto);

	op.addr.buswidth = spi_nor_get_protocol_addr_nbits(read->proto);

	op.data.buswidth = spi_nor_get_protocol_data_nbits(read->proto);

	op.dummy.buswidth = op.addr.buswidth;

	op.dummy.nbytes = (read->num_mode_clocks + read->num_wait_states) *

			  op.dummy.buswidth / 8;



	return spi_nor_spimem_check_op(nor, &op);

}



/**

 * spi_nor_spimem_check_pp - check if the page program op is supported

 *                           by controller

 *@nor:         pointer to a 'struct spi_nor'

 *@pp:          pointer to op template to be checked

 *

 * Returns 0 if operation is supported, -ENOTSUPP otherwise.

 */

static int spi_nor_spimem_check_pp(struct spi_nor *nor,

				   const struct spi_nor_pp_command *pp)

{

	struct spi_mem_op op = SPI_MEM_OP(SPI_MEM_OP_CMD(pp->opcode, 1),

					  SPI_MEM_OP_ADDR(3, 0, 1),

					  SPI_MEM_OP_NO_DUMMY,

					  SPI_MEM_OP_DATA_OUT(0, NULL, 1));



	op.cmd.buswidth = spi_nor_get_protocol_inst_nbits(pp->proto);

	op.addr.buswidth = spi_nor_get_protocol_addr_nbits(pp->proto);

	op.data.buswidth = spi_nor_get_protocol_data_nbits(pp->proto);



	return spi_nor_spimem_check_op(nor, &op);

}



/**

 * spi_nor_spimem_adjust_hwcaps - Find optimal Read/Write protocol

 *                                based on SPI controller capabilities

 * @nor:        pointer to a 'struct spi_nor'

 * @params:     pointer to the 'struct spi_nor_flash_parameter'

 *              representing SPI NOR flash capabilities

 * @hwcaps:     pointer to resulting capabilities after adjusting

 *              according to controller and flash's capability

 */

static void

spi_nor_spimem_adjust_hwcaps(struct spi_nor *nor,

			     const struct spi_nor_flash_parameter *params,

			     u32 *hwcaps)

{

	unsigned int cap;



	/* DTR modes are not supported yet, mask them all. */

	*hwcaps &= ~SNOR_HWCAPS_DTR;



	/* X-X-X modes are not supported yet, mask them all. */

	*hwcaps &= ~SNOR_HWCAPS_X_X_X;



	for (cap = 0; cap < sizeof(*hwcaps) * BITS_PER_BYTE; cap++) {

		int rdidx, ppidx;



		if (!(*hwcaps & BIT(cap)))

			continue;



		rdidx = spi_nor_hwcaps_read2cmd(BIT(cap));

		if (rdidx >= 0 &&

		    spi_nor_spimem_check_readop(nor, &params->reads[rdidx]))

			*hwcaps &= ~BIT(cap);



		ppidx = spi_nor_hwcaps_pp2cmd(BIT(cap));

		if (ppidx < 0)

			continue;



		if (spi_nor_spimem_check_pp(nor,

					    &params->page_programs[ppidx]))

			*hwcaps &= ~BIT(cap);

	}

}



/**

 * spi_nor_read_sfdp_dma_unsafe() - read Serial Flash Discoverable Parameters.

 * @nor:	pointer to a 'struct spi_nor'
@@ -4360,17 +4483,26 @@ static int spi_nor_setup(struct spi_nor *nor, 
	 */

	shared_mask = hwcaps->mask & params->hwcaps.mask;



	/* SPI n-n-n protocols are not supported yet. */

	ignored_mask = (SNOR_HWCAPS_READ_2_2_2 |

			SNOR_HWCAPS_READ_4_4_4 |

			SNOR_HWCAPS_READ_8_8_8 |

			SNOR_HWCAPS_PP_4_4_4 |

			SNOR_HWCAPS_PP_8_8_8);

	if (nor->spimem) {

		/*

		 * When called from spi_nor_probe(), all caps are set and we

		 * need to discard some of them based on what the SPI

		 * controller actually supports (using spi_mem_supports_op()).

		 */

		spi_nor_spimem_adjust_hwcaps(nor, params, &shared_mask);

	} else {

		/*

		 * SPI n-n-n protocols are not supported when the SPI

		 * controller directly implements the spi_nor interface.

		 * Yet another reason to switch to spi-mem.

		 */

		ignored_mask = SNOR_HWCAPS_X_X_X;

		if (shared_mask & ignored_mask) {

			dev_dbg(nor->dev,

			"SPI n-n-n protocols are not supported yet.\n");

				"SPI n-n-n protocols are not supported.\n");

			shared_mask &= ~ignored_mask;

		}

	}



	/* Select the (Fast) Read command. */

	err = spi_nor_select_read(nor, params, shared_mask);
@@ -4712,11 +4844,11 @@ static int spi_nor_probe(struct spi_mem *spimem) 
	struct spi_device *spi = spimem->spi;

	struct flash_platform_data *data = dev_get_platdata(&spi->dev);

	struct spi_nor *nor;

	struct spi_nor_hwcaps hwcaps = {

		.mask = SNOR_HWCAPS_READ |

			SNOR_HWCAPS_READ_FAST |

			SNOR_HWCAPS_PP,

	};

	/*

	 * Enable all caps by default. The core will mask them after

	 * checking what's really supported using spi_mem_supports_op().

	 */

	const struct spi_nor_hwcaps hwcaps = { .mask = SNOR_HWCAPS_ALL };

	char *flash_name;

	int ret;
@@ -4730,27 +4862,6 @@ static int spi_nor_probe(struct spi_mem *spimem) 


	spi_mem_set_drvdata(spimem, nor);



	if (spi->mode & SPI_RX_OCTAL) {

		hwcaps.mask |= SNOR_HWCAPS_READ_1_1_8;



		if (spi->mode & SPI_TX_OCTAL)

			hwcaps.mask |= (SNOR_HWCAPS_READ_1_8_8 |

					SNOR_HWCAPS_PP_1_1_8 |

					SNOR_HWCAPS_PP_1_8_8);

	} else if (spi->mode & SPI_RX_QUAD) {

		hwcaps.mask |= SNOR_HWCAPS_READ_1_1_4;



		if (spi->mode & SPI_TX_QUAD)

			hwcaps.mask |= (SNOR_HWCAPS_READ_1_4_4 |

					SNOR_HWCAPS_PP_1_1_4 |

					SNOR_HWCAPS_PP_1_4_4);

	} else if (spi->mode & SPI_RX_DUAL) {

		hwcaps.mask |= SNOR_HWCAPS_READ_1_1_2;



		if (spi->mode & SPI_TX_DUAL)

			hwcaps.mask |= SNOR_HWCAPS_READ_1_2_2;

	}



	if (data && data->name)

		nor->mtd.name = data->name;

include/linux/mtd/spi-nor.h

+14 −0
Original line number Diff line number Diff line
@@ -524,6 +524,20 @@ struct spi_nor_hwcaps { 
#define SNOR_HWCAPS_PP_1_8_8	BIT(21)

#define SNOR_HWCAPS_PP_8_8_8	BIT(22)



#define SNOR_HWCAPS_X_X_X	(SNOR_HWCAPS_READ_2_2_2 |	\

				 SNOR_HWCAPS_READ_4_4_4 |	\

				 SNOR_HWCAPS_READ_8_8_8 |	\

				 SNOR_HWCAPS_PP_4_4_4 |		\

				 SNOR_HWCAPS_PP_8_8_8)



#define SNOR_HWCAPS_DTR		(SNOR_HWCAPS_READ_1_1_1_DTR |	\

				 SNOR_HWCAPS_READ_1_2_2_DTR |	\

				 SNOR_HWCAPS_READ_1_4_4_DTR |	\

				 SNOR_HWCAPS_READ_1_8_8_DTR)



#define SNOR_HWCAPS_ALL		(SNOR_HWCAPS_READ_MASK |	\

				 SNOR_HWCAPS_PP_MASK)



/**

 * spi_nor_scan() - scan the SPI NOR

 * @nor:	the spi_nor structure