[PATCH v3 06/14] mtd: spi-nor: sfdp: get octal mode maximum speed from BFPT

From: Mason Yang
Date: Thu May 28 2020 - 03:59:03 EST


Get maximum operation speed of device in octal mode from
BFPT 20th DWORD.

Signed-off-by: Mason Yang <masonccyang@xxxxxxxxxxx>
---
drivers/mtd/spi-nor/core.h | 2 ++
drivers/mtd/spi-nor/sfdp.c | 36 ++++++++++++++++++++++++++++++++++++
drivers/mtd/spi-nor/sfdp.h | 4 ++++
3 files changed, 42 insertions(+)

diff --git a/drivers/mtd/spi-nor/core.h b/drivers/mtd/spi-nor/core.h
index de1e391..f644ed1 100644
--- a/drivers/mtd/spi-nor/core.h
+++ b/drivers/mtd/spi-nor/core.h
@@ -192,6 +192,7 @@ struct spi_nor_locking_ops {
*
* @size: the flash memory density in bytes.
* @page_size: the page size of the SPI NOR flash memory.
+ * @octal_max_speed: maximum operation speed of device in octal mode.
* @hwcaps: describes the read and page program hardware
* capabilities.
* @reads: read capabilities ordered by priority: the higher index
@@ -214,6 +215,7 @@ struct spi_nor_locking_ops {
struct spi_nor_flash_parameter {
u64 size;
u32 page_size;
+ u16 octal_max_speed;

struct spi_nor_hwcaps hwcaps;
struct spi_nor_read_command reads[SNOR_CMD_READ_MAX];
diff --git a/drivers/mtd/spi-nor/sfdp.c b/drivers/mtd/spi-nor/sfdp.c
index 3685a3a..d7ef47a 100644
--- a/drivers/mtd/spi-nor/sfdp.c
+++ b/drivers/mtd/spi-nor/sfdp.c
@@ -4,6 +4,7 @@
* Copyright (C) 2014, Freescale Semiconductor, Inc.
*/

+#include <linux/bitfield.h>
#include <linux/slab.h>
#include <linux/sort.h>
#include <linux/mtd/spi-nor.h>
@@ -26,6 +27,12 @@
#define SFDP_JESD216A_MINOR 5
#define SFDP_JESD216B_MINOR 6

+/* Basic Flash Parameter Table 20th DWORD, Max operation speed of device */
+struct octal_max_speed {
+ u8 idx; /* Bits value */
+ u16 hz; /* MHz */
+};
+
struct sfdp_header {
u32 signature; /* Ox50444653U <=> "SFDP" */
u8 minor;
@@ -440,6 +447,22 @@ static int spi_nor_parse_bfpt(struct spi_nor *nor,
u32 addr;
u16 half;
u8 erase_mask;
+ static const struct octal_max_speed max_hz[] = {
+ /* Bits value, MHz */
+ { 0x0c, 400 },
+ { 0x0b, 333 },
+ { 0x0a, 266 },
+ { 0x09, 250 },
+ { 0x08, 200 },
+ { 0x07, 166 },
+ { 0x06, 133 },
+ { 0x05, 100 },
+ { 0x04, 80 },
+ { 0x03, 66 },
+ { 0x02, 50 },
+ { 0x01, 33 },
+ };
+ u8 idx;

/* JESD216 Basic Flash Parameter Table length is at least 9 DWORDs. */
if (bfpt_header->length < BFPT_DWORD_MAX_JESD216)
@@ -626,6 +649,19 @@ static int spi_nor_parse_bfpt(struct spi_nor *nor,
return -ENOTSUPP;
}

+ /* Octal mode max speed */
+ idx = max(FIELD_GET(BFPT_DWORD20_OCTAL_DTR_MAX_SPEED,
+ bfpt.dwords[BFPT_DWORD(20)]),
+ FIELD_GET(BFPT_DWORD20_OCTAL_STR_MAX_SPEED,
+ bfpt.dwords[BFPT_DWORD(20)]));
+
+ for (i = 0; i < ARRAY_SIZE(max_hz); i++) {
+ if (max_hz[i].idx == idx) {
+ params->octal_max_speed = max_hz[i].hz;
+ break;
+ }
+ }
+
return spi_nor_post_bfpt_fixups(nor, bfpt_header, &bfpt, params);
}

diff --git a/drivers/mtd/spi-nor/sfdp.h b/drivers/mtd/spi-nor/sfdp.h
index e15e307..d8ee681 100644
--- a/drivers/mtd/spi-nor/sfdp.h
+++ b/drivers/mtd/spi-nor/sfdp.h
@@ -90,6 +90,10 @@ struct sfdp_bfpt {
#define BFPT_DWORD18_CMD_EXT_RES (0x2UL << 29) /* Reserved */
#define BFPT_DWORD18_CMD_EXT_16B (0x3UL << 29) /* 16-bit opcode */

+#define BFPT_DWORD20_OCTAL_MAX_SPEED_MASK GENMASK(31, 16)
+#define BFPT_DWORD20_OCTAL_DTR_MAX_SPEED GENMASK(31, 28)
+#define BFPT_DWORD20_OCTAL_STR_MAX_SPEED GENMASK(19, 16)
+
struct sfdp_parameter_header {
u8 id_lsb;
u8 minor;
--
1.9.1