[PATCH v2 2/2] Implement SDHCI CQE support for DesignWare SDHCI.
From: Sergey Khimich
Date: Tue Sep 26 2023 - 05:02:57 EST
From: Sergey Khimich <serghox@xxxxxxxxx>
For enabling CQE support just set 'supports-cqe' in your DevTree file
for appropriate mmc node.
Signed-off-by: Sergey Khimich <serghox@xxxxxxxxx>
---
drivers/mmc/host/Kconfig | 1 +
drivers/mmc/host/sdhci-of-dwcmshc.c | 233 +++++++++++++++++++++++++++-
2 files changed, 232 insertions(+), 2 deletions(-)
diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index 554e67103c1a..f3380b014ca9 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -233,6 +233,7 @@ config MMC_SDHCI_OF_DWCMSHC
depends on MMC_SDHCI_PLTFM
depends on OF
depends on COMMON_CLK
+ select MMC_CQHCI
help
This selects Synopsys DesignWare Cores Mobile Storage Controller
support.
diff --git a/drivers/mmc/host/sdhci-of-dwcmshc.c b/drivers/mmc/host/sdhci-of-dwcmshc.c
index 3a3bae6948a8..7d43ae011811 100644
--- a/drivers/mmc/host/sdhci-of-dwcmshc.c
+++ b/drivers/mmc/host/sdhci-of-dwcmshc.c
@@ -20,6 +20,7 @@
#include <linux/sizes.h>
#include "sdhci-pltfm.h"
+#include "cqhci.h"
#define SDHCI_DWCMSHC_ARG2_STUFF GENMASK(31, 16)
@@ -36,6 +37,9 @@
#define DWCMSHC_ENHANCED_STROBE BIT(8)
#define DWCMSHC_EMMC_ATCTRL 0x40
+/* DWC IP vendor area 2 pointer */
+#define DWCMSHC_P_VENDOR_AREA2 0xea
+
/* Rockchip specific Registers */
#define DWCMSHC_EMMC_DLL_CTRL 0x800
#define DWCMSHC_EMMC_DLL_RXCLK 0x804
@@ -75,6 +79,10 @@
#define BOUNDARY_OK(addr, len) \
((addr | (SZ_128M - 1)) == ((addr + len - 1) | (SZ_128M - 1)))
+#define DWCMSHC_SDHCI_CQE_TRNS_MODE (SDHCI_TRNS_MULTI | \
+ SDHCI_TRNS_BLK_CNT_EN | \
+ SDHCI_TRNS_DMA)
+
enum dwcmshc_rk_type {
DWCMSHC_RK3568,
DWCMSHC_RK3588,
@@ -90,7 +98,8 @@ struct rk35xx_priv {
struct dwcmshc_priv {
struct clk *bus_clk;
- int vendor_specific_area1; /* P_VENDOR_SPECIFIC_AREA reg */
+ int vendor_specific_area1; /* P_VENDOR_SPECIFIC_AREA1 reg */
+ int vendor_specific_area2; /* P_VENDOR_SPECIFIC_AREA2 reg */
void *priv; /* pointer to SoC private stuff */
};
@@ -210,6 +219,147 @@ static void dwcmshc_hs400_enhanced_strobe(struct mmc_host *mmc,
sdhci_writel(host, vendor, reg);
}
+static u32 dwcmshc_cqe_irq_handler(struct sdhci_host *host, u32 intmask)
+{
+ int cmd_error = 0;
+ int data_error = 0;
+
+ if (!sdhci_cqe_irq(host, intmask, &cmd_error, &data_error))
+ return intmask;
+
+ cqhci_irq(host->mmc, intmask, cmd_error, data_error);
+
+ return 0;
+}
+
+static void dwcmshc_sdhci_cqe_enable(struct mmc_host *mmc)
+{
+ struct sdhci_host *host = mmc_priv(mmc);
+ u32 pstate;
+ u8 ctrl;
+ int count = 10;
+
+ /*
+ * CQE gets stuck if it sees Buffer Read Enable bit set, which can be
+ * the case after tuning, so ensure the buffer is drained.
+ */
+ pstate = sdhci_readl(host, SDHCI_PRESENT_STATE);
+ while (pstate & SDHCI_DATA_AVAILABLE) {
+ sdhci_readl(host, SDHCI_BUFFER);
+ pstate = sdhci_readl(host, SDHCI_PRESENT_STATE);
+ if (count-- == 0) {
+ dev_warn(mmc_dev(host->mmc),
+ "CQE may get stuck because the Buffer Read Enable bit is set\n");
+ break;
+ }
+ mdelay(1);
+ }
+
+ sdhci_writew(host, DWCMSHC_SDHCI_CQE_TRNS_MODE, SDHCI_TRANSFER_MODE);
+
+ sdhci_cqe_enable(mmc);
+
+ /*
+ * The "DesignWare Cores Mobile Storage Host Controller
+ * DWC_mshc / DWC_mshc_lite Databook" says:
+ * when Host Version 4 Enable" is 1 in Host Control 2 register,
+ * SDHCI_CTRL_ADMA32 bit means ADMA2 is selected.
+ * Selection of 32-bit/64-bit System Addressing:
+ * either 32-bit or 64-bit system addressing is selected by
+ * 64-bit Addressing bit in Host Control 2 register.
+ *
+ * On the other hand the "DesignWare Cores Mobile Storage Host
+ * Controller DWC_mshc / DWC_mshc_lite User Guide" says, that we have to
+ * set DMA_SEL to ADMA2 _only_ mode in the Host Control 2 register.
+ */
+ ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL);
+ ctrl &= ~SDHCI_CTRL_DMA_MASK;
+ ctrl |= SDHCI_CTRL_ADMA32;
+ sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
+}
+
+static void dwcmshc_sdhci_cqe_disable(struct mmc_host *mmc, bool recovery)
+{
+ /*
+ * If an ioctl was issued, cqe_disable will be called.
+ * For CQE of sdhci-of-dwcmshc, the previous in-flight cmd will be lost quietly.
+ * So wait for mmc idle state.
+ */
+ mmc->cqe_ops->cqe_wait_for_idle(mmc);
+
+ return sdhci_cqe_disable(mmc, recovery);
+}
+
+static void dwcmshc_cqhci_set_tran_desc(u8 *desc, dma_addr_t addr, int len, bool end,
+ bool dma64)
+{
+ __le32 *attr = (__le32 __force *)desc;
+
+ *attr = (CQHCI_VALID(1) |
+ CQHCI_END(end ? 1 : 0) |
+ CQHCI_INT(0) |
+ CQHCI_ACT(0x4) |
+ CQHCI_DAT_LENGTH(len));
+
+ if (dma64) {
+ __le64 *dataddr = (__le64 __force *)(desc + 4);
+
+ dataddr[0] = cpu_to_le64(addr);
+ } else {
+ __le32 *dataddr = (__le32 __force *)(desc + 4);
+
+ dataddr[0] = cpu_to_le32(addr);
+ }
+}
+
+static void dwcmshc_cqhci_prep_tran_desc(struct mmc_data *data,
+ struct cqhci_host *cq_host,
+ u8 *desc, int sg_count)
+{
+ int i, len, tmplen, offset;
+ bool end = false;
+ bool dma64 = cq_host->dma64;
+ dma_addr_t addr;
+ struct scatterlist *sg;
+
+ for_each_sg(data->sg, sg, sg_count, i) {
+ addr = sg_dma_address(sg);
+ len = sg_dma_len(sg);
+
+ /*
+ * According to the "DesignWare Cores Mobile Storage Host Controller
+ * DWC_mshc / DWC_mshc_lite Databook" the host memory data buffer size
+ * and start address must not exceed 128 Mb. If it exceeds,
+ * the data buffer must be split using two descritors.
+ */
+
+ if (likely(BOUNDARY_OK(addr, len))) {
+ if ((i + 1) == sg_count)
+ end = true;
+ dwcmshc_cqhci_set_tran_desc(desc, addr, len, end, dma64);
+ desc += cq_host->trans_desc_len;
+ } else {
+ offset = addr & (SZ_128M - 1);
+ tmplen = SZ_128M - offset;
+ dwcmshc_cqhci_set_tran_desc(desc, addr, tmplen, end, dma64);
+ desc += cq_host->trans_desc_len;
+
+ if ((i + 1) == sg_count)
+ end = true;
+
+ addr += tmplen;
+ len -= tmplen;
+ dwcmshc_cqhci_set_tran_desc(desc, addr, len, end, dma64);
+ desc += cq_host->trans_desc_len;
+ }
+ }
+}
+
+static void dwcmshc_cqhci_dumpregs(struct mmc_host *mmc)
+{
+ sdhci_dumpregs(mmc_priv(mmc));
+}
+
static void dwcmshc_rk3568_set_clock(struct sdhci_host *host, unsigned int clock)
{
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
@@ -345,6 +495,7 @@ static const struct sdhci_ops sdhci_dwcmshc_ops = {
.get_max_clock = dwcmshc_get_max_clock,
.reset = sdhci_reset,
.adma_write_desc = dwcmshc_adma_write_desc,
+ .irq = dwcmshc_cqe_irq_handler,
};
static const struct sdhci_ops sdhci_dwcmshc_rk35xx_ops = {
@@ -379,6 +530,70 @@ static const struct sdhci_pltfm_data sdhci_dwcmshc_rk35xx_pdata = {
SDHCI_QUIRK2_CLOCK_DIV_ZERO_BROKEN,
};
+static const struct cqhci_host_ops dwcmshc_cqhci_ops = {
+ .enable = dwcmshc_sdhci_cqe_enable,
+ .disable = dwcmshc_sdhci_cqe_disable,
+ .dumpregs = dwcmshc_cqhci_dumpregs,
+ .prep_tran_desc = dwcmshc_cqhci_prep_tran_desc,
+};
+
+static void dwcmshc_cqhci_init(struct sdhci_host *host, struct platform_device *pdev)
+{
+ struct cqhci_host *cq_host;
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ struct dwcmshc_priv *priv = sdhci_pltfm_priv(pltfm_host);
+ bool dma64 = false;
+ u16 clk;
+ int err;
+
+ host->mmc->caps2 |= MMC_CAP2_CQE | MMC_CAP2_CQE_DCMD;
+ cq_host = devm_kzalloc(&pdev->dev, sizeof(*cq_host), GFP_KERNEL);
+ if (!cq_host) {
+ dev_err(mmc_dev(host->mmc), "Unable to setup CQE: not enough memory\n");
+ return;
+ }
+
+ /*
+ * For dwcmshc host controller we have to enable internal clock
+ * before access to some registers from Vendor Specific Aria 2.
+ */
+ clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
+ clk |= SDHCI_CLOCK_INT_EN;
+ sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
+ clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
+ if (!(clk & SDHCI_CLOCK_INT_EN)) {
+ dev_err(mmc_dev(host->mmc), "Unable to setup CQE: internal clock enable error\n");
+ goto free_cq_host;
+ }
+
+ cq_host->mmio = host->ioaddr + priv->vendor_specific_area2;
+ cq_host->ops = &dwcmshc_cqhci_ops;
+
+ /* Enable using of 128-bit task descriptors */
+ dma64 = host->flags & SDHCI_USE_64_BIT_DMA;
+ if (dma64) {
+ dev_dbg(mmc_dev(host->mmc), "128-bit task descriptors\n");
+ cq_host->caps |= CQHCI_TASK_DESC_SZ_128;
+ }
+ err = cqhci_init(cq_host, host->mmc, dma64);
+ if (err) {
+ dev_err(mmc_dev(host->mmc), "Unable to setup CQE: error %d\n", err);
+ goto int_clok_disable;
+ }
+
+ dev_dbg(mmc_dev(host->mmc), "CQE init done\n");
+
+ return;
+
+int_clok_disable:
+ clk = sdhci_readw(host, SDHCI_CLOCK_CONTROL);
+ clk &= ~SDHCI_CLOCK_INT_EN;
+ sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
+
+free_cq_host:
+ devm_kfree(&pdev->dev, cq_host);
+}
+
static int dwcmshc_rk35xx_init(struct sdhci_host *host, struct dwcmshc_priv *dwc_priv)
{
int err;
@@ -471,7 +686,7 @@ static int dwcmshc_probe(struct platform_device *pdev)
struct rk35xx_priv *rk_priv = NULL;
const struct sdhci_pltfm_data *pltfm_data;
int err;
- u32 extra;
+ u32 extra, caps;
pltfm_data = device_get_match_data(&pdev->dev);
if (!pltfm_data) {
@@ -519,6 +734,8 @@ static int dwcmshc_probe(struct platform_device *pdev)
priv->vendor_specific_area1 =
sdhci_readl(host, DWCMSHC_P_VENDOR_AREA1) & DWCMSHC_AREA1_MASK;
+ priv->vendor_specific_area2 =
+ sdhci_readw(host, DWCMSHC_P_VENDOR_AREA2);
host->mmc_host_ops.request = dwcmshc_request;
host->mmc_host_ops.hs400_enhanced_strobe = dwcmshc_hs400_enhanced_strobe;
@@ -547,6 +764,10 @@ static int dwcmshc_probe(struct platform_device *pdev)
sdhci_enable_v4_mode(host);
#endif
+ caps = sdhci_readl(host, SDHCI_CAPABILITIES);
+ if (caps & SDHCI_CAN_64BIT_V4)
+ sdhci_enable_v4_mode(host);
+
host->mmc->caps |= MMC_CAP_WAIT_WHILE_BUSY;
pm_runtime_get_noresume(dev);
@@ -557,6 +778,14 @@ static int dwcmshc_probe(struct platform_device *pdev)
if (err)
goto err_rpm;
+ /* Setup Command Queue Engine if enabled */
+ if (device_property_read_bool(&pdev->dev, "supports-cqe")) {
+ if (caps & SDHCI_CAN_64BIT_V4)
+ dwcmshc_cqhci_init(host, pdev);
+ else
+ dev_warn(dev, "Cannot enable CQE without V4 mode support\n");
+ }
+
if (rk_priv)
dwcmshc_rk35xx_postinit(host, priv);
--
2.30.2