[PATCH 10/11] mmc: core: Read performance enhancements registers for SD cards
From: Ulf Hansson
Date: Tue May 04 2021 - 12:13:24 EST
In SD spec v6.x the SD function extension registers for performance
enhancements were introduced. These registers let the SD card announce
supports for various performance related features, like "self-maintenance",
"cache" and "command queuing".
Let's extend the parsing of SD function extension registers and store the
information in the struct mmc_card. This prepares for subsequent changes to
implement the complete support for new the performance enhancement
features.
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
---
drivers/mmc/core/sd.c | 53 ++++++++++++++++++++++++++++++++++++++++
include/linux/mmc/card.h | 7 ++++++
2 files changed, 60 insertions(+)
diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c
index cb5e8b2fc32f..702d7c1a0aec 100644
--- a/drivers/mmc/core/sd.c
+++ b/drivers/mmc/core/sd.c
@@ -1058,6 +1058,55 @@ static int sd_parse_ext_reg_power(struct mmc_card *card, u8 fno, u8 page,
return err;
}
+static int sd_parse_ext_reg_perf(struct mmc_card *card, u8 fno, u8 page,
+ u16 offset)
+{
+ int err;
+ u8 *reg_buf;
+
+ reg_buf = kzalloc(512, GFP_KERNEL);
+ if (!reg_buf)
+ return -ENOMEM;
+
+ err = sd_read_ext_reg(card, fno, page, offset, 512, reg_buf);
+ if (err) {
+ pr_warn("%s: error %d reading PERF func of ext reg\n",
+ mmc_hostname(card->host), err);
+ goto out;
+ }
+
+ /* PERF revision. */
+ card->ext_perf.rev = reg_buf[0];
+
+ /* FX_EVENT support at bit 0. */
+ if (reg_buf[1] & 0x1)
+ card->ext_perf.feature_support |= SD_EXT_PERF_FX_EVENT;
+
+ /* Card initiated self-maintenance support at bit 0. */
+ if (reg_buf[2] & 0x1)
+ card->ext_perf.feature_support |= SD_EXT_PERF_CARD_MAINT;
+
+ /* Host initiated self-maintenance support at bit 1. */
+ if (reg_buf[2] & 0x2)
+ card->ext_perf.feature_support |= SD_EXT_PERF_HOST_MAINT;
+
+ /* Cache support at bit 0. */
+ if (reg_buf[4] & 0x1)
+ card->ext_perf.feature_support |= SD_EXT_PERF_CACHE;
+
+ /* Command queue support indicated via queue depth bits (0 to 4). */
+ if (reg_buf[6] & 0x1f)
+ card->ext_perf.feature_support |= SD_EXT_PERF_CMD_QUEUE;
+
+ card->ext_perf.fno = fno;
+ card->ext_perf.page = page;
+ card->ext_perf.offset = offset;
+
+out:
+ kfree(reg_buf);
+ return err;
+}
+
static int sd_parse_ext_reg(struct mmc_card *card, u8 *gen_info_buf,
u16 *next_ext_addr)
{
@@ -1102,6 +1151,10 @@ static int sd_parse_ext_reg(struct mmc_card *card, u8 *gen_info_buf,
if (sfc == 0x1)
return sd_parse_ext_reg_power(card, fno, page, offset);
+ /* Standard Function Code for performance enhancement. */
+ if (sfc == 0x2)
+ return sd_parse_ext_reg_perf(card, fno, page, offset);
+
return 0;
}
diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h
index 03a862e93594..2867af0635f8 100644
--- a/include/linux/mmc/card.h
+++ b/include/linux/mmc/card.h
@@ -201,6 +201,12 @@ struct sd_ext_reg {
#define SD_EXT_POWER_OFF_NOTIFY (1<<0)
#define SD_EXT_POWER_SUSTENANCE (1<<1)
#define SD_EXT_POWER_DOWN_MODE (1<<2)
+/* Performance Enhancement Function. */
+#define SD_EXT_PERF_FX_EVENT (1<<0)
+#define SD_EXT_PERF_CARD_MAINT (1<<1)
+#define SD_EXT_PERF_HOST_MAINT (1<<2)
+#define SD_EXT_PERF_CACHE (1<<3)
+#define SD_EXT_PERF_CMD_QUEUE (1<<4)
};
struct sdio_cccr {
@@ -305,6 +311,7 @@ struct mmc_card {
struct sd_ssr ssr; /* yet more SD information */
struct sd_switch_caps sw_caps; /* switch (CMD6) caps */
struct sd_ext_reg ext_power; /* SD extension reg for PM */
+ struct sd_ext_reg ext_perf; /* SD extension reg for PERF */
unsigned int sdio_funcs; /* number of SDIO functions */
atomic_t sdio_funcs_probed; /* number of probed SDIO funcs */
--
2.25.1