Unverified Commit 0f698d74 authored by Jonas Gorski's avatar Jonas Gorski Committed by Mark Brown
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spi: bcm63xx-hsspi: add support for 1-2-2 read ops 



Add support for 1-2-2 read ops by separately calculating the switch from
single-bit to multi-bit, and then switching within the prepend data.

This allows us to support single-bit write followed by multi-bit write
followed by multi-bit read, and we do not need to reject 1-2-2 read
operations anymore.

Tested on BCM963268BU_P300 with custom fixup to allow 1-2-2 on the
non-SDFP capable s25fl129p1 attached (which it actually supports):

root@OpenWrt:~# cat /sys/kernel/debug/spi-nor/spi1.0/params
name            s25fl129p1
id              01 20 18 4d 01 01
size            16.0 MiB
write size      1
page size       256
address nbytes  3
flags           HAS_16BIT_SR | NO_READ_CR

opcodes
 read           0xbb
  dummy cycles  4
 erase          0xd8
 program        0x02
 8D extension   none

protocols
 read           1S-2S-2S
 write          1S-1S-1S
 register       1S-1S-1S

Reading from flash is still working as expected:

[    1.070000] parser_imagetag: rootfs: CFE image tag found at 0x0 with version 6, board type 963168VX
[    1.080000] parser_imagetag: Partition 0 is rootfs offset 100 and length 665000
[    1.090000] parser_imagetag: Partition 1 is kernel offset 665100 and length 136fa1
[    1.100000] parser_imagetag: Spare partition is offset 7b0000 and length 30000

Signed-off-by: default avatarJonas Gorski <jonas.gorski@gmail.com>
Acked-by: default avatarWilliam Zhang <william.zhang@broadcom.com>
Tested-by: default avatarDavid Regan <dregan@broadcom.com>
Link: https://patch.msgid.link/20251217211026.173946-1-jonas.gorski@gmail.com


Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent 458800ea

drivers/spi/spi-bcm63xx-hsspi.c

+41 −23
Original line number Diff line number Diff line
@@ -142,6 +142,7 @@ struct bcm63xx_hsspi { 
	u32 wait_mode;

	u32 xfer_mode;

	u32 prepend_cnt;

	u32 md_start;

	u8 *prepend_buf;

};
@@ -268,18 +269,20 @@ static bool bcm63xx_prepare_prepend_transfer(struct spi_controller *host, 
{



	struct bcm63xx_hsspi *bs = spi_controller_get_devdata(host);

	bool tx_only = false;

	bool tx_only = false, multidata = false;

	struct spi_transfer *t;



	/*

	 * Multiple transfers within a message may be combined into one transfer

	 * to the controller using its prepend feature. A SPI message is prependable

	 * only if the following are all true:

	 *   1. One or more half duplex write transfer in single bit mode

	 *   2. Optional full duplex read/write at the end

	 *   3. No delay and cs_change between transfers

	 *   1. One or more half duplex write transfers at the start

	 *   2. Optional switch from single to dual bit within the write transfers

	 *   3. Optional full duplex read/write at the end if all single bit

	 *   4. No delay and cs_change between transfers

	 */

	bs->prepend_cnt = 0;

	bs->md_start = 0;

	list_for_each_entry(t, &msg->transfers, transfer_list) {

		if ((spi_delay_to_ns(&t->delay, t) > 0) || t->cs_change) {

			bcm63xx_prepend_printk_on_checkfail(bs,
@@ -297,31 +300,44 @@ static bool bcm63xx_prepare_prepend_transfer(struct spi_controller *host, 
				return false;

			}



			if (t->tx_nbits > SPI_NBITS_SINGLE &&

				!list_is_last(&t->transfer_list, &msg->transfers)) {

			if (t->tx_nbits == SPI_NBITS_SINGLE &&

			    !list_is_last(&t->transfer_list, &msg->transfers) &&

			    multidata) {

				bcm63xx_prepend_printk_on_checkfail(bs,

					 "multi-bit prepend buf not supported!\n");

					 "single-bit after multi-bit not supported!\n");

				return false;

			}



			if (t->tx_nbits == SPI_NBITS_SINGLE) {

			if (t->tx_nbits > SPI_NBITS_SINGLE)

				multidata = true;



			memcpy(bs->prepend_buf + bs->prepend_cnt, t->tx_buf, t->len);

			bs->prepend_cnt += t->len;

			}



			if (t->tx_nbits == SPI_NBITS_SINGLE)

				bs->md_start += t->len;



		} else {

			if (!list_is_last(&t->transfer_list, &msg->transfers)) {

				bcm63xx_prepend_printk_on_checkfail(bs,

					 "rx/tx_rx transfer not supported when it is not last one!\n");

				return false;

			}



			if (t->rx_buf && t->rx_nbits == SPI_NBITS_SINGLE &&

			    multidata) {

				bcm63xx_prepend_printk_on_checkfail(bs,

					 "single-bit after multi-bit not supported!\n");

				return false;

			}

		}



		if (list_is_last(&t->transfer_list, &msg->transfers)) {

			memcpy(t_prepend, t, sizeof(struct spi_transfer));



			if (tx_only && t->tx_nbits == SPI_NBITS_SINGLE) {

			if (tx_only) {

				/*

				 * if the last one is also a single bit tx only transfer, merge

				 * if the last one is also a tx only transfer, merge

				 * all of them into one single tx transfer

				 */

				t_prepend->len = bs->prepend_cnt;
@@ -329,7 +345,7 @@ static bool bcm63xx_prepare_prepend_transfer(struct spi_controller *host, 
				bs->prepend_cnt = 0;

			} else {

				/*

				 * if the last one is not a tx only transfer or dual tx xfer, all

				 * if the last one is not a tx only transfer, all

				 * the previous transfers are sent through prepend bytes and

				 * make sure it does not exceed the max prepend len

				 */
@@ -339,6 +355,15 @@ static bool bcm63xx_prepare_prepend_transfer(struct spi_controller *host, 
					return false;

				}

			}

			/*

			 * If switching from single-bit to multi-bit, make sure

			 * the start offset does not exceed the maximum

			 */

			if (multidata && bs->md_start > HSSPI_MAX_PREPEND_LEN) {

				bcm63xx_prepend_printk_on_checkfail(bs,

					"exceed max multi-bit offset, abort prepending transfers!\n");

				return false;

			}

		}

	}
@@ -381,11 +406,11 @@ static int bcm63xx_hsspi_do_prepend_txrx(struct spi_device *spi, 


		if (t->rx_nbits == SPI_NBITS_DUAL) {

			reg |= 1 << MODE_CTRL_MULTIDATA_RD_SIZE_SHIFT;

			reg |= bs->prepend_cnt << MODE_CTRL_MULTIDATA_RD_STRT_SHIFT;

			reg |= bs->md_start << MODE_CTRL_MULTIDATA_RD_STRT_SHIFT;

		}

		if (t->tx_nbits == SPI_NBITS_DUAL) {

			reg |= 1 << MODE_CTRL_MULTIDATA_WR_SIZE_SHIFT;

			reg |= bs->prepend_cnt << MODE_CTRL_MULTIDATA_WR_STRT_SHIFT;

			reg |= bs->md_start << MODE_CTRL_MULTIDATA_WR_STRT_SHIFT;

		}

	}
@@ -692,13 +717,6 @@ static bool bcm63xx_hsspi_mem_supports_op(struct spi_mem *mem, 
	if (!spi_mem_default_supports_op(mem, op))

		return false;



	/* Controller doesn't support spi mem dual io mode */

	if ((op->cmd.opcode == SPINOR_OP_READ_1_2_2) ||

		(op->cmd.opcode == SPINOR_OP_READ_1_2_2_4B) ||

		(op->cmd.opcode == SPINOR_OP_READ_1_2_2_DTR) ||

		(op->cmd.opcode == SPINOR_OP_READ_1_2_2_DTR_4B))

		return false;



	return true;

}