[PATCH v5] mtd: rawnand: brcmnand: legacy exec_op implementation

Álvaro Fernández Rojas
2025-05-21T08:03:36Z

Commit 3c8260ce7663 ("mtd: rawnand: brcmnand: exec_op implementation")
removed legacy interface functions, breaking < v5.0 controllers support.
In order to fix older controllers we need to add an alternative exec_op
implementation which doesn't rely on low level registers.

Fixes: 3c8260ce7663 ("mtd: rawnand: brcmnand: exec_op implementation")
Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
Reviewed-by: David Regan <dregan@broadcom.com>
---
drivers/mtd/nand/raw/brcmnand/brcmnand.c | 222 ++++++++++++++++++++++-
1 file changed, 215 insertions(+), 7 deletions(-)

v5: add changes requested by Miquèl Raynal:
- Mention and explain legacy in native_cmd_conv.
- EOPNOTSUPP instead of EINVAL for instr->type else.
- Implement missing check_only functionality.

v4: add changes requested by Jonas Gorski:
- Add missing breaks in brcmnand_exec_instructions_legacy.
- Restore missing ret assignment in brcmnand_exec_op.

v3: add changes requested by Florian and other improvements:
- Add associative array for native command conversion.
- Add function pointer to brcmnand_controller for exec_instr
functionality.
- Fix CMD_BLOCK_ERASE address.
- Drop NAND_CMD_READOOB support.

v2: multiple improvements:
- Use proper native commands for checks.
- Fix NAND_CMD_PARAM/NAND_CMD_RNDOUT addr calculation.
- Remove host->last_addr usage.
- Remove sector_size_1k since it only applies to v5.0+ controllers.
- Remove brcmnand_wp since it doesn't exist for < v5.0 controllers.
- Use j instead of i for flash_cache loop.

diff --git a/drivers/mtd/nand/raw/brcmnand/brcmnand.c b/drivers/mtd/nand/raw/brcmnand/brcmnand.c
index 299dd2bca5b4..5ed79ffa271c 100644
--- a/drivers/mtd/nand/raw/brcmnand/brcmnand.c
+++ b/drivers/mtd/nand/raw/brcmnand/brcmnand.c
@@ -65,6 +65,7 @@ module_param(wp_on, int, 0444);
#define CMD_PARAMETER_READ 0x0e
#define CMD_PARAMETER_CHANGE_COL 0x0f
#define CMD_LOW_LEVEL_OP 0x10
+#define CMD_NOT_SUPPORTED 0xff

struct brcm_nand_dma_desc {
u32 next_desc;
@@ -199,6 +200,30 @@ static const u16 flash_dma_regs_v4[] = {
[FLASH_DMA_CURRENT_DESC_EXT] = 0x34,
};

+/* Native command conversion for legacy controllers (< v5.0) */
+static const u8 native_cmd_conv[] = {
+ [NAND_CMD_READ0] = CMD_NOT_SUPPORTED,
+ [NAND_CMD_READ1] = CMD_NOT_SUPPORTED,
+ [NAND_CMD_RNDOUT] = CMD_PARAMETER_CHANGE_COL,
+ [NAND_CMD_PAGEPROG] = CMD_NOT_SUPPORTED,
+ [NAND_CMD_READOOB] = CMD_NOT_SUPPORTED,
+ [NAND_CMD_ERASE1] = CMD_BLOCK_ERASE,
+ [NAND_CMD_STATUS] = CMD_NOT_SUPPORTED,
+ [NAND_CMD_SEQIN] = CMD_NOT_SUPPORTED,
+ [NAND_CMD_RNDIN] = CMD_NOT_SUPPORTED,
+ [NAND_CMD_READID] = CMD_DEVICE_ID_READ,
+ [NAND_CMD_ERASE2] = CMD_NULL,
+ [NAND_CMD_PARAM] = CMD_PARAMETER_READ,
+ [NAND_CMD_GET_FEATURES] = CMD_NOT_SUPPORTED,
+ [NAND_CMD_SET_FEATURES] = CMD_NOT_SUPPORTED,
+ [NAND_CMD_RESET] = CMD_NOT_SUPPORTED,
+ [NAND_CMD_READSTART] = CMD_NOT_SUPPORTED,
+ [NAND_CMD_READCACHESEQ] = CMD_NOT_SUPPORTED,
+ [NAND_CMD_READCACHEEND] = CMD_NOT_SUPPORTED,
+ [NAND_CMD_RNDOUTSTART] = CMD_NULL,
+ [NAND_CMD_CACHEDPROG] = CMD_NOT_SUPPORTED,
+};
+
/* Controller feature flags */
enum {
BRCMNAND_HAS_1K_SECTORS = BIT(0),
@@ -237,6 +262,12 @@ struct brcmnand_controller {
/* List of NAND hosts (one for each chip-select) */
struct list_head host_list;

+ /* Functions to be called from exec_op */
+ int (*check_instr)(struct nand_chip *chip,
+ const struct nand_operation *op);
+ int (*exec_instr)(struct nand_chip *chip,
+ const struct nand_operation *op);
+
/* EDU info, per-transaction */
const u16 *edu_offsets;
void __iomem *edu_base;
@@ -2478,18 +2509,190 @@ static int brcmnand_op_is_reset(const struct nand_operation *op)
return 0;
}

+static int brcmnand_check_instructions(struct nand_chip *chip,
+ const struct nand_operation *op)
+{
+ return 0;
+}
+
+static int brcmnand_exec_instructions(struct nand_chip *chip,
+ const struct nand_operation *op)
+{
+ struct brcmnand_host *host = nand_get_controller_data(chip);
+ unsigned int i;
+ int ret = 0;
+
+ for (i = 0; i < op->ninstrs; i++) {
+ ret = brcmnand_exec_instr(host, i, op);
+ if (ret)
+ break;
+ }
+
+ return ret;
+}
+
+static int brcmnand_check_instructions_legacy(struct nand_chip *chip,
+ const struct nand_operation *op)
+{
+ const struct nand_op_instr *instr;
+ unsigned int i;
+ u8 cmd;
+
+ for (i = 0; i < op->ninstrs; i++) {
+ instr = &op->instrs[i];
+
+ switch (instr->type) {
+ case NAND_OP_CMD_INSTR:
+ cmd = native_cmd_conv[instr->ctx.cmd.opcode];
+ if (cmd == CMD_NOT_SUPPORTED)
+ return -EOPNOTSUPP;
+ break;
+ case NAND_OP_ADDR_INSTR:
+ case NAND_OP_DATA_IN_INSTR:
+ case NAND_OP_WAITRDY_INSTR:
+ break;
+ default:
+ return -EOPNOTSUPP;
+ }
+ }
+
+ return 0;
+}
+
+static int brcmnand_exec_instructions_legacy(struct nand_chip *chip,
+ const struct nand_operation *op)
+{
+ struct mtd_info *mtd = nand_to_mtd(chip);
+ struct brcmnand_host *host = nand_get_controller_data(chip);
+ struct brcmnand_controller *ctrl = host->ctrl;
+ const struct nand_op_instr *instr;
+ unsigned int i, j;
+ u8 cmd = CMD_NULL, last_cmd = CMD_NULL;
+ int ret = 0;
+ u64 last_addr;
+
+ for (i = 0; i < op->ninstrs; i++) {
+ instr = &op->instrs[i];
+
+ if (instr->type == NAND_OP_CMD_INSTR) {
+ cmd = native_cmd_conv[instr->ctx.cmd.opcode];
+ if (cmd == CMD_NOT_SUPPORTED) {
+ dev_err(ctrl->dev, "unsupported cmd=%d\n",
+ instr->ctx.cmd.opcode);
+ ret = -EOPNOTSUPP;
+ break;
+ }
+ } else if (instr->type == NAND_OP_ADDR_INSTR) {
+ u64 addr = 0;
+
+ if (cmd == CMD_NULL)
+ continue;
+
+ if (instr->ctx.addr.naddrs > 8) {
+ dev_err(ctrl->dev, "unsupported naddrs=%u\n",
+ instr->ctx.addr.naddrs);
+ ret = -EOPNOTSUPP;
+ break;
+ }
+
+ for (j = 0; j < instr->ctx.addr.naddrs; j++)
+ addr |= (instr->ctx.addr.addrs[j]) << (j << 3);
+
+ if (cmd == CMD_BLOCK_ERASE)
+ addr <<= chip->page_shift;
+ else if (cmd == CMD_PARAMETER_CHANGE_COL)
+ addr &= ~((u64)(FC_BYTES - 1));
+
+ brcmnand_set_cmd_addr(mtd, addr);
+ brcmnand_send_cmd(host, cmd);
+ last_addr = addr;
+ last_cmd = cmd;
+ cmd = CMD_NULL;
+ brcmnand_waitfunc(chip);
+
+ if (last_cmd == CMD_PARAMETER_READ ||
+ last_cmd == CMD_PARAMETER_CHANGE_COL) {
+ /* Copy flash cache word-wise */
+ u32 *flash_cache = (u32 *)ctrl->flash_cache;
+
+ brcmnand_soc_data_bus_prepare(ctrl->soc, true);
+
+ /*
+ * Must cache the FLASH_CACHE now, since changes in
+ * SECTOR_SIZE_1K may invalidate it
+ */
+ for (j = 0; j < FC_WORDS; j++)
+ /*
+ * Flash cache is big endian for parameter pages, at
+ * least on STB SoCs
+ */
+ flash_cache[j] = be32_to_cpu(brcmnand_read_fc(ctrl, j));
+
+ brcmnand_soc_data_bus_unprepare(ctrl->soc, true);
+ }
+ } else if (instr->type == NAND_OP_DATA_IN_INSTR) {
+ u8 *in = instr->ctx.data.buf.in;
+
+ if (last_cmd == CMD_DEVICE_ID_READ) {
+ u32 val;
+
+ if (instr->ctx.data.len > 8) {
+ dev_err(ctrl->dev, "unsupported len=%u\n",
+ instr->ctx.data.len);
+ ret = -EOPNOTSUPP;
+ break;
+ }
+
+ for (j = 0; j < instr->ctx.data.len; j++) {
+ if (j == 0)
+ val = brcmnand_read_reg(ctrl, BRCMNAND_ID);
+ else if (j == 4)
+ val = brcmnand_read_reg(ctrl, BRCMNAND_ID_EXT);
+
+ in[j] = (val >> (24 - ((j % 4) << 3))) & 0xff;
+ }
+ } else if (last_cmd == CMD_PARAMETER_READ ||
+ last_cmd == CMD_PARAMETER_CHANGE_COL) {
+ u64 addr;
+ u32 offs;
+
+ for (j = 0; j < instr->ctx.data.len; j++) {
+ addr = last_addr + j;
+ offs = addr & (FC_BYTES - 1);
+
+ if (j > 0 && offs == 0)
+ nand_change_read_column_op(chip, addr, NULL, 0,
+ false);
+
+ in[j] = ctrl->flash_cache[offs];
+ }
+ }
+ } else if (instr->type == NAND_OP_WAITRDY_INSTR) {
+ ret = bcmnand_ctrl_poll_status(host, NAND_CTRL_RDY, NAND_CTRL_RDY, 0);
+ if (ret)
+ break;
+ } else {
+ dev_err(ctrl->dev, "unsupported instruction type: %d\n", instr->type);
+ ret = -EOPNOTSUPP;
+ break;
+ }
+ }
+
+ return ret;
+}
+
static int brcmnand_exec_op(struct nand_chip *chip,
const struct nand_operation *op,
bool check_only)
{
struct brcmnand_host *host = nand_get_controller_data(chip);
+ struct brcmnand_controller *ctrl = host->ctrl;
struct mtd_info *mtd = nand_to_mtd(chip);
u8 *status;
- unsigned int i;
int ret = 0;

if (check_only)
- return 0;
+ return ctrl->check_instr(chip, op);

if (brcmnand_op_is_status(op)) {
status = op->instrs[1].ctx.data.buf.in;
@@ -2513,11 +2716,7 @@ static int brcmnand_exec_op(struct nand_chip *chip,
if (op->deassert_wp)
brcmnand_wp(mtd, 0);

- for (i = 0; i < op->ninstrs; i++) {
- ret = brcmnand_exec_instr(host, i, op);
- if (ret)
- break;
- }
+ ret = ctrl->exec_instr(chip, op);

if (op->deassert_wp)
brcmnand_wp(mtd, 1);
@@ -3130,6 +3329,15 @@ int brcmnand_probe(struct platform_device *pdev, struct brcmnand_soc *soc)
if (ret)
goto err;

+ /* Only v5.0+ controllers have low level ops support */
+ if (ctrl->nand_version >= 0x0500) {
+ ctrl->check_instr = brcmnand_check_instructions;
+ ctrl->exec_instr = brcmnand_exec_instructions;
+ } else {
+ ctrl->check_instr = brcmnand_check_instructions_legacy;
+ ctrl->exec_instr = brcmnand_exec_instructions_legacy;
+ }
+
/*
* Most chips have this cache at a fixed offset within 'nand' block.
* Some must specify this region separately.
--
2.39.5