[PATCH V6 4/9] mmc: sdhci: Add ADMA2 64-bit addressing support for V4 mode
From: Chunyan Zhang
Date: Fri Aug 24 2018 - 05:21:37 EST
ADMA2 64-bit addressing support is divided into V3 mode and V4 mode.
So there are two kinds of descriptors for ADMA2 64-bit addressing
i.e. 96-bit Descriptor for V3 mode, and 128-bit Descriptor for V4
mode. 128-bit Descriptor is aligned to 8-byte.
For V4 mode, ADMA2 64-bit addressing is enabled via Host Control 2
register.
Signed-off-by: Chunyan Zhang <zhang.chunyan@xxxxxxxxxx>
---
drivers/mmc/host/sdhci.c | 92 +++++++++++++++++++++++++++++++++++-------------
drivers/mmc/host/sdhci.h | 12 +++++--
2 files changed, 78 insertions(+), 26 deletions(-)
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index df283ca..38d083c 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -266,6 +266,52 @@ static void sdhci_set_default_irqs(struct sdhci_host *host)
sdhci_writel(host, host->ier, SDHCI_SIGNAL_ENABLE);
}
+static void sdhci_config_dma(struct sdhci_host *host)
+{
+ u8 ctrl;
+ u16 ctrl2;
+
+ if (host->version < SDHCI_SPEC_200)
+ return;
+
+ ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL);
+
+ /*
+ * Always adjust the DMA selection as some controllers
+ * (e.g. JMicron) can't do PIO properly when the selection
+ * is ADMA.
+ */
+ ctrl &= ~SDHCI_CTRL_DMA_MASK;
+ if (!(host->flags & SDHCI_REQ_USE_DMA))
+ goto out;
+
+ /* Note if DMA Select is zero then SDMA is selected */
+ if (host->flags & SDHCI_USE_ADMA)
+ ctrl |= SDHCI_CTRL_ADMA32;
+
+ if (host->flags & SDHCI_USE_64_BIT_DMA) {
+ /*
+ * If v4 mode, all supported DMA can be 64-bit addressing if
+ * controller supports 64-bit system address, otherwise only
+ * ADMA can support 64-bit addressing.
+ */
+ if (host->v4_mode) {
+ ctrl2 = sdhci_readw(host, SDHCI_HOST_CONTROL2);
+ ctrl2 |= SDHCI_CTRL_64BIT_ADDR;
+ sdhci_writew(host, ctrl2, SDHCI_HOST_CONTROL2);
+ } else if (host->flags & SDHCI_USE_ADMA) {
+ /*
+ * Don't need to undo SDHCI_CTRL_ADMA32 in order to
+ * set SDHCI_CTRL_ADMA64.
+ */
+ ctrl |= SDHCI_CTRL_ADMA64;
+ }
+ }
+
+out:
+ sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
+}
+
static void sdhci_init(struct sdhci_host *host, int soft)
{
struct mmc_host *mmc = host->mmc;
@@ -913,7 +959,6 @@ static void sdhci_set_timeout(struct sdhci_host *host, struct mmc_command *cmd)
static void sdhci_prepare_data(struct sdhci_host *host, struct mmc_command *cmd)
{
- u8 ctrl;
struct mmc_data *data = cmd->data;
host->data_timeout = 0;
@@ -1009,25 +1054,7 @@ static void sdhci_prepare_data(struct sdhci_host *host, struct mmc_command *cmd)
}
}
- /*
- * Always adjust the DMA selection as some controllers
- * (e.g. JMicron) can't do PIO properly when the selection
- * is ADMA.
- */
- if (host->version >= SDHCI_SPEC_200) {
- ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL);
- ctrl &= ~SDHCI_CTRL_DMA_MASK;
- if ((host->flags & SDHCI_REQ_USE_DMA) &&
- (host->flags & SDHCI_USE_ADMA)) {
- if (host->flags & SDHCI_USE_64_BIT_DMA)
- ctrl |= SDHCI_CTRL_ADMA64;
- else
- ctrl |= SDHCI_CTRL_ADMA32;
- } else {
- ctrl |= SDHCI_CTRL_SDMA;
- }
- sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
- }
+ sdhci_config_dma(host);
if (!(host->flags & SDHCI_REQ_USE_DMA)) {
int flags;
@@ -3504,6 +3531,19 @@ static int sdhci_allocate_bounce_buffer(struct sdhci_host *host)
return 0;
}
+static inline bool sdhci_can_64bit_dma(struct sdhci_host *host)
+{
+ /*
+ * According to SD Host Controller spec v4.10, bit[27] added from
+ * version 4.10 in Capabilities Register is used as 64-bit System
+ * Address support for V4 mode.
+ */
+ if (host->version >= SDHCI_SPEC_410 && host->v4_mode)
+ return host->caps & SDHCI_CAN_64BIT_V4;
+
+ return host->caps & SDHCI_CAN_64BIT;
+}
+
int sdhci_setup_host(struct sdhci_host *host)
{
struct mmc_host *mmc;
@@ -3575,7 +3615,7 @@ int sdhci_setup_host(struct sdhci_host *host)
* SDHCI_QUIRK2_BROKEN_64_BIT_DMA must be left to the drivers to
* implement.
*/
- if (host->caps & SDHCI_CAN_64BIT)
+ if (sdhci_can_64bit_dma(host))
host->flags |= SDHCI_USE_64_BIT_DMA;
if (host->flags & (SDHCI_USE_SDMA | SDHCI_USE_ADMA)) {
@@ -3609,8 +3649,8 @@ int sdhci_setup_host(struct sdhci_host *host)
*/
if (host->flags & SDHCI_USE_64_BIT_DMA) {
host->adma_table_sz = (SDHCI_MAX_SEGS * 2 + 1) *
- SDHCI_ADMA2_64_DESC_SZ;
- host->desc_sz = SDHCI_ADMA2_64_DESC_SZ;
+ SDHCI_ADMA2_64_DESC_SZ(host);
+ host->desc_sz = SDHCI_ADMA2_64_DESC_SZ(host);
} else {
host->adma_table_sz = (SDHCI_MAX_SEGS * 2 + 1) *
SDHCI_ADMA2_32_DESC_SZ;
@@ -3618,7 +3658,11 @@ int sdhci_setup_host(struct sdhci_host *host)
}
host->align_buffer_sz = SDHCI_MAX_SEGS * SDHCI_ADMA2_ALIGN;
- buf = dma_alloc_coherent(mmc_dev(mmc), host->align_buffer_sz +
+ /*
+ * Use zalloc to zero the reserved high 32-bits of 128-bit
+ * descriptors so that they never need to be written.
+ */
+ buf = dma_zalloc_coherent(mmc_dev(mmc), host->align_buffer_sz +
host->adma_table_sz, &dma, GFP_KERNEL);
if (!buf) {
pr_warn("%s: Unable to allocate ADMA buffers - falling back to standard DMA\n",
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index 131d869..f3b9ebc 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -185,6 +185,7 @@
#define SDHCI_CTRL_EXEC_TUNING 0x0040
#define SDHCI_CTRL_TUNED_CLK 0x0080
#define SDHCI_CTRL_V4_MODE 0x1000
+#define SDHCI_CTRL_64BIT_ADDR 0x2000
#define SDHCI_CTRL_PRESET_VAL_ENABLE 0x8000
#define SDHCI_CAPABILITIES 0x40
@@ -205,6 +206,7 @@
#define SDHCI_CAN_VDD_330 0x01000000
#define SDHCI_CAN_VDD_300 0x02000000
#define SDHCI_CAN_VDD_180 0x04000000
+#define SDHCI_CAN_64BIT_V4 0x08000000
#define SDHCI_CAN_64BIT 0x10000000
#define SDHCI_SUPPORT_SDR50 0x00000001
@@ -309,8 +311,14 @@ struct sdhci_adma2_32_desc {
*/
#define SDHCI_ADMA2_DESC_ALIGN 8
-/* ADMA2 64-bit DMA descriptor size */
-#define SDHCI_ADMA2_64_DESC_SZ 12
+/*
+ * ADMA2 64-bit DMA descriptor size
+ * According to SD Host Controller spec v4.10, there are two kinds of
+ * descriptors for 64-bit addressing mode: 96-bit Descriptor and 128-bit
+ * Descriptor, if Host Version 4 Enable is set in the Host Control 2
+ * register, 128-bit Descriptor will be selected.
+ */
+#define SDHCI_ADMA2_64_DESC_SZ(host) ((host)->v4_mode ? 16 : 12)
/*
* ADMA2 64-bit descriptor. Note 12-byte descriptor can't always be 8-byte
--
2.7.4