[PATCH v2 06/12] drivers/soc: Add Aspeed XDMA Engine Driver

From: Eddie James
Date: Thu Dec 05 2019 - 12:15:45 EST


The XDMA engine embedded in the AST2500 and AST2600 SOCs performs PCI
DMA operations between the SOC (acting as a BMC) and a host processor
in a server.

This commit adds a driver to control the XDMA engine and adds functions
to initialize the hardware and memory and start DMA operations.

Signed-off-by: Eddie James <eajames@xxxxxxxxxxxxx>
---
Changes since v1:
- Add lock comments
- Don't split reset into start/finish
- Drop client_lock as the new reset method means client data is safe
- Switch to a chip structure to control versions rather than enum/switch
- Drop in_progress bool in favor or current_client being NULL or not
- Get SDRAM controller from dts phandle
- Configure PCI-E based on dts property
- Get VGA memory space from dts property
- Drop bmc_addr from aspeed_xdma_op as mmap can do all that

MAINTAINERS | 2 +
drivers/soc/aspeed/Kconfig | 8 +
drivers/soc/aspeed/Makefile | 1 +
drivers/soc/aspeed/aspeed-xdma.c | 783 +++++++++++++++++++++++++++++++++++++++
include/uapi/linux/aspeed-xdma.h | 41 ++
5 files changed, 835 insertions(+)
create mode 100644 drivers/soc/aspeed/aspeed-xdma.c
create mode 100644 include/uapi/linux/aspeed-xdma.h

diff --git a/MAINTAINERS b/MAINTAINERS
index 528a142..617c03d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2712,6 +2712,8 @@ M: Eddie James <eajames@xxxxxxxxxxxxx>
L: linux-aspeed@xxxxxxxxxxxxxxxx (moderated for non-subscribers)
S: Maintained
F: Documentation/devicetree/bindings/soc/aspeed/xdma.txt
+F: drivers/soc/aspeed/aspeed-xdma.c
+F: include/uapi/linux/aspeed-xdma.h

ASUS NOTEBOOKS AND EEEPC ACPI/WMI EXTRAS DRIVERS
M: Corentin Chary <corentin.chary@xxxxxxxxx>
diff --git a/drivers/soc/aspeed/Kconfig b/drivers/soc/aspeed/Kconfig
index 323e177..2a6c16f 100644
--- a/drivers/soc/aspeed/Kconfig
+++ b/drivers/soc/aspeed/Kconfig
@@ -29,4 +29,12 @@ config ASPEED_P2A_CTRL
ioctl()s, the driver also provides an interface for userspace mappings to
a pre-defined region.

+config ASPEED_XDMA
+ tristate "Aspeed XDMA Engine Driver"
+ depends on SOC_ASPEED && REGMAP && MFD_SYSCON && HAS_DMA
+ help
+ Enable support for the Aspeed XDMA Engine found on the Aspeed AST2XXX
+ SOCs. The XDMA engine can perform automatic PCI DMA operations
+ between the AST2XXX (acting as a BMC) and a host processor.
+
endmenu
diff --git a/drivers/soc/aspeed/Makefile b/drivers/soc/aspeed/Makefile
index b64be47..977b046 100644
--- a/drivers/soc/aspeed/Makefile
+++ b/drivers/soc/aspeed/Makefile
@@ -2,3 +2,4 @@
obj-$(CONFIG_ASPEED_LPC_CTRL) += aspeed-lpc-ctrl.o
obj-$(CONFIG_ASPEED_LPC_SNOOP) += aspeed-lpc-snoop.o
obj-$(CONFIG_ASPEED_P2A_CTRL) += aspeed-p2a-ctrl.o
+obj-$(CONFIG_ASPEED_XDMA) += aspeed-xdma.o
diff --git a/drivers/soc/aspeed/aspeed-xdma.c b/drivers/soc/aspeed/aspeed-xdma.c
new file mode 100644
index 0000000..a9b3eeb
--- /dev/null
+++ b/drivers/soc/aspeed/aspeed-xdma.c
@@ -0,0 +1,783 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+// Copyright IBM Corp 2019
+
+#include <linux/aspeed-xdma.h>
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/fs.h>
+#include <linux/genalloc.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/jiffies.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/poll.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/string.h>
+#include <linux/uaccess.h>
+#include <linux/wait.h>
+#include <linux/workqueue.h>
+
+#define DEVICE_NAME "aspeed-xdma"
+
+#define SCU_AST2500_PCIE_CONF 0x180
+#define SCU_AST2600_PCIE_CONF 0xc20
+#define SCU_PCIE_CONF_VGA_EN BIT(0)
+#define SCU_PCIE_CONF_VGA_EN_MMIO BIT(1)
+#define SCU_PCIE_CONF_VGA_EN_LPC BIT(2)
+#define SCU_PCIE_CONF_VGA_EN_MSI BIT(3)
+#define SCU_PCIE_CONF_VGA_EN_MCTP BIT(4)
+#define SCU_PCIE_CONF_VGA_EN_IRQ BIT(5)
+#define SCU_PCIE_CONF_VGA_EN_DMA BIT(6)
+#define SCU_PCIE_CONF_BMC_EN BIT(8)
+#define SCU_PCIE_CONF_BMC_EN_MMIO BIT(9)
+#define SCU_PCIE_CONF_BMC_EN_MSI BIT(11)
+#define SCU_PCIE_CONF_BMC_EN_MCTP BIT(12)
+#define SCU_PCIE_CONF_BMC_EN_IRQ BIT(13)
+#define SCU_PCIE_CONF_BMC_EN_DMA BIT(14)
+
+#define SCU_AST2500_BMC_CLASS_REV 0x19c
+#define SCU_AST2600_BMC_CLASS_REV 0xc4c
+#define SCU_BMC_CLASS_REV_XDMA 0xff000001
+
+#define SDMC_REMAP 0x008
+#define SDMC_AST2500_REMAP_PCIE BIT(16)
+#define SDMC_AST2500_REMAP_XDMA BIT(17)
+#define SDMC_AST2600_REMAP_XDMA BIT(18)
+
+#define XDMA_CMDQ_SIZE PAGE_SIZE
+#define XDMA_NUM_CMDS \
+ (XDMA_CMDQ_SIZE / sizeof(struct aspeed_xdma_cmd))
+
+/* Aspeed specification requires 10ms after switching the reset line */
+#define XDMA_RESET_TIME_MS 10
+
+#define XDMA_CMD_AST2500_PITCH_SHIFT 3
+#define XDMA_CMD_AST2500_PITCH_BMC GENMASK_ULL(62, 51)
+#define XDMA_CMD_AST2500_PITCH_HOST GENMASK_ULL(46, 35)
+#define XDMA_CMD_AST2500_PITCH_UPSTREAM BIT_ULL(31)
+#define XDMA_CMD_AST2500_PITCH_ADDR GENMASK_ULL(29, 4)
+#define XDMA_CMD_AST2500_PITCH_ID BIT_ULL(0)
+#define XDMA_CMD_AST2500_CMD_IRQ_EN BIT_ULL(31)
+#define XDMA_CMD_AST2500_CMD_LINE_NO GENMASK_ULL(27, 16)
+#define XDMA_CMD_AST2500_CMD_IRQ_BMC BIT_ULL(15)
+#define XDMA_CMD_AST2500_CMD_LINE_SIZE_SHIFT 4
+#define XDMA_CMD_AST2500_CMD_LINE_SIZE \
+ GENMASK_ULL(14, XDMA_CMD_AST2500_CMD_LINE_SIZE_SHIFT)
+#define XDMA_CMD_AST2500_CMD_ID BIT_ULL(1)
+
+#define XDMA_CMD_AST2600_PITCH_BMC GENMASK_ULL(62, 48)
+#define XDMA_CMD_AST2600_PITCH_HOST GENMASK_ULL(46, 32)
+#define XDMA_CMD_AST2600_PITCH_ADDR GENMASK_ULL(30, 0)
+#define XDMA_CMD_AST2600_CMD_64_EN BIT_ULL(40)
+#define XDMA_CMD_AST2600_CMD_IRQ_BMC BIT_ULL(37)
+#define XDMA_CMD_AST2600_CMD_IRQ_HOST BIT_ULL(36)
+#define XDMA_CMD_AST2600_CMD_UPSTREAM BIT_ULL(32)
+#define XDMA_CMD_AST2600_CMD_LINE_NO GENMASK_ULL(27, 16)
+#define XDMA_CMD_AST2600_CMD_LINE_SIZE GENMASK_ULL(14, 0)
+#define XDMA_CMD_AST2600_CMD_MULTILINE_SIZE GENMASK_ULL(14, 12)
+
+#define XDMA_AST2500_QUEUE_ENTRY_SIZE 4
+#define XDMA_AST2500_HOST_CMDQ_ADDR0 0x00
+#define XDMA_AST2500_HOST_CMDQ_ENDP 0x04
+#define XDMA_AST2500_HOST_CMDQ_WRITEP 0x08
+#define XDMA_AST2500_HOST_CMDQ_READP 0x0c
+#define XDMA_AST2500_BMC_CMDQ_ADDR 0x10
+#define XDMA_AST2500_BMC_CMDQ_ENDP 0x14
+#define XDMA_AST2500_BMC_CMDQ_WRITEP 0x18
+#define XDMA_AST2500_BMC_CMDQ_READP 0x1c
+#define XDMA_BMC_CMDQ_READP_RESET 0xee882266
+#define XDMA_AST2500_CTRL 0x20
+#define XDMA_AST2500_CTRL_US_COMP BIT(4)
+#define XDMA_AST2500_CTRL_DS_COMP BIT(5)
+#define XDMA_AST2500_CTRL_DS_DIRTY BIT(6)
+#define XDMA_AST2500_CTRL_DS_SIZE_256 BIT(17)
+#define XDMA_AST2500_CTRL_DS_TIMEOUT BIT(28)
+#define XDMA_AST2500_CTRL_DS_CHECK_ID BIT(29)
+#define XDMA_AST2500_STATUS 0x24
+#define XDMA_AST2500_STATUS_US_COMP BIT(4)
+#define XDMA_AST2500_STATUS_DS_COMP BIT(5)
+#define XDMA_AST2500_STATUS_DS_DIRTY BIT(6)
+#define XDMA_AST2500_INPRG_DS_CMD1 0x38
+#define XDMA_AST2500_INPRG_DS_CMD2 0x3c
+#define XDMA_AST2500_INPRG_US_CMD00 0x40
+#define XDMA_AST2500_INPRG_US_CMD01 0x44
+#define XDMA_AST2500_INPRG_US_CMD10 0x48
+#define XDMA_AST2500_INPRG_US_CMD11 0x4c
+#define XDMA_AST2500_INPRG_US_CMD20 0x50
+#define XDMA_AST2500_INPRG_US_CMD21 0x54
+#define XDMA_AST2500_HOST_CMDQ_ADDR1 0x60
+#define XDMA_AST2500_VGA_CMDQ_ADDR0 0x64
+#define XDMA_AST2500_VGA_CMDQ_ENDP 0x68
+#define XDMA_AST2500_VGA_CMDQ_WRITEP 0x6c
+#define XDMA_AST2500_VGA_CMDQ_READP 0x70
+#define XDMA_AST2500_VGA_CMD_STATUS 0x74
+#define XDMA_AST2500_VGA_CMDQ_ADDR1 0x78
+
+#define XDMA_AST2600_QUEUE_ENTRY_SIZE 2
+#define XDMA_AST2600_HOST_CMDQ_ADDR0 0x00
+#define XDMA_AST2600_HOST_CMDQ_ADDR1 0x04
+#define XDMA_AST2600_HOST_CMDQ_ENDP 0x08
+#define XDMA_AST2600_HOST_CMDQ_WRITEP 0x0c
+#define XDMA_AST2600_HOST_CMDQ_READP 0x10
+#define XDMA_AST2600_BMC_CMDQ_ADDR 0x14
+#define XDMA_AST2600_BMC_CMDQ_ENDP 0x18
+#define XDMA_AST2600_BMC_CMDQ_WRITEP 0x1c
+#define XDMA_AST2600_BMC_CMDQ_READP 0x20
+#define XDMA_AST2600_VGA_CMDQ_ADDR0 0x24
+#define XDMA_AST2600_VGA_CMDQ_ADDR1 0x28
+#define XDMA_AST2600_VGA_CMDQ_ENDP 0x2c
+#define XDMA_AST2600_VGA_CMDQ_WRITEP 0x30
+#define XDMA_AST2600_VGA_CMDQ_READP 0x34
+#define XDMA_AST2600_CTRL 0x38
+#define XDMA_AST2600_CTRL_US_COMP BIT(16)
+#define XDMA_AST2600_CTRL_DS_COMP BIT(17)
+#define XDMA_AST2600_CTRL_DS_DIRTY BIT(18)
+#define XDMA_AST2600_CTRL_DS_SIZE_256 BIT(20)
+#define XDMA_AST2600_STATUS 0x3c
+#define XDMA_AST2600_STATUS_US_COMP BIT(16)
+#define XDMA_AST2600_STATUS_DS_COMP BIT(17)
+#define XDMA_AST2600_STATUS_DS_DIRTY BIT(18)
+#define XDMA_AST2600_INPRG_DS_CMD00 0x40
+#define XDMA_AST2600_INPRG_DS_CMD01 0x44
+#define XDMA_AST2600_INPRG_DS_CMD10 0x48
+#define XDMA_AST2600_INPRG_DS_CMD11 0x4c
+#define XDMA_AST2600_INPRG_DS_CMD20 0x50
+#define XDMA_AST2600_INPRG_DS_CMD21 0x54
+#define XDMA_AST2600_INPRG_US_CMD00 0x60
+#define XDMA_AST2600_INPRG_US_CMD01 0x64
+#define XDMA_AST2600_INPRG_US_CMD10 0x68
+#define XDMA_AST2600_INPRG_US_CMD11 0x6c
+#define XDMA_AST2600_INPRG_US_CMD20 0x70
+#define XDMA_AST2600_INPRG_US_CMD21 0x74
+
+struct aspeed_xdma_cmd {
+ u64 host_addr;
+ u64 pitch;
+ u64 cmd;
+ u64 reserved;
+};
+
+struct aspeed_xdma_regs {
+ u8 bmc_cmdq_addr;
+ u8 bmc_cmdq_endp;
+ u8 bmc_cmdq_writep;
+ u8 bmc_cmdq_readp;
+ u8 control;
+ u8 status;
+};
+
+struct aspeed_xdma_status_bits {
+ u32 us_comp;
+ u32 ds_comp;
+ u32 ds_dirty;
+};
+
+struct aspeed_xdma;
+
+struct aspeed_xdma_chip {
+ u32 control;
+ u32 scu_bmc_class;
+ u32 scu_pcie_conf;
+ u32 sdmc_remap;
+ unsigned int queue_entry_size;
+ struct aspeed_xdma_regs regs;
+ struct aspeed_xdma_status_bits status_bits;
+ unsigned int (*set_cmd)(struct aspeed_xdma *ctx,
+ struct aspeed_xdma_op *op, u32 bmc_addr);
+};
+
+struct aspeed_xdma_client;
+
+struct aspeed_xdma {
+ const struct aspeed_xdma_chip *chip;
+
+ struct device *dev;
+ void __iomem *base;
+ struct clk *clock;
+ struct reset_control *reset;
+
+ struct aspeed_xdma_client *current_client;
+
+ /* start_lock protects cmd_idx, cmdq, and the state of the engine */
+ struct mutex start_lock;
+ void *cmdq;
+ bool in_reset;
+ bool upstream;
+ unsigned int cmd_idx;
+
+ /* reset_lock protects in_reset and the reset state of the engine */
+ spinlock_t reset_lock;
+
+ wait_queue_head_t wait;
+ struct work_struct reset_work;
+
+ u32 vga_phys;
+ u32 vga_size;
+ void __iomem *vga_virt;
+ dma_addr_t cmdq_vga_phys;
+ void *cmdq_vga_virt;
+ struct gen_pool *vga_pool;
+};
+
+struct aspeed_xdma_client {
+ struct aspeed_xdma *ctx;
+
+ bool error;
+ bool in_progress;
+ void *virt;
+ dma_addr_t phys;
+ u32 size;
+};
+
+static u32 aspeed_xdma_readl(struct aspeed_xdma *ctx, u8 reg)
+{
+ u32 v = readl(ctx->base + reg);
+
+ dev_dbg(ctx->dev, "read %02x[%08x]\n", reg, v);
+ return v;
+}
+
+static void aspeed_xdma_writel(struct aspeed_xdma *ctx, u8 reg, u32 val)
+{
+ writel(val, ctx->base + reg);
+ dev_dbg(ctx->dev, "write %02x[%08x]\n", reg, val);
+}
+
+static void aspeed_xdma_init_eng(struct aspeed_xdma *ctx)
+{
+ aspeed_xdma_writel(ctx, ctx->chip->regs.bmc_cmdq_endp,
+ ctx->chip->queue_entry_size * XDMA_NUM_CMDS);
+ aspeed_xdma_writel(ctx, ctx->chip->regs.bmc_cmdq_readp,
+ XDMA_BMC_CMDQ_READP_RESET);
+ aspeed_xdma_writel(ctx, ctx->chip->regs.bmc_cmdq_writep, 0);
+ aspeed_xdma_writel(ctx, ctx->chip->regs.control, ctx->chip->control);
+ aspeed_xdma_writel(ctx, ctx->chip->regs.bmc_cmdq_addr,
+ ctx->cmdq_vga_phys);
+
+ ctx->cmd_idx = 0;
+ ctx->current_client = NULL;
+}
+
+static unsigned int aspeed_xdma_ast2500_set_cmd(struct aspeed_xdma *ctx,
+ struct aspeed_xdma_op *op,
+ u32 bmc_addr)
+{
+ u64 cmd = XDMA_CMD_AST2500_CMD_IRQ_EN | XDMA_CMD_AST2500_CMD_IRQ_BMC |
+ XDMA_CMD_AST2500_CMD_ID;
+ u64 cmd_pitch = (op->direction ? XDMA_CMD_AST2500_PITCH_UPSTREAM : 0) |
+ XDMA_CMD_AST2500_PITCH_ID;
+ unsigned int line_size;
+ unsigned int nidx = (ctx->cmd_idx + 1) % XDMA_NUM_CMDS;
+ unsigned int line_no = 1;
+ unsigned int pitch = 1;
+ struct aspeed_xdma_cmd *ncmd =
+ &(((struct aspeed_xdma_cmd *)ctx->cmdq)[ctx->cmd_idx]);
+
+ dev_dbg(ctx->dev, "xdma %s ast2500: bmc[%08x] len[%08x] host[%08x]\n",
+ op->direction ? "upstream" : "downstream", bmc_addr, op->len,
+ (u32)op->host_addr);
+
+ if (op->len > XDMA_CMD_AST2500_CMD_LINE_SIZE) {
+ unsigned int rem;
+ unsigned int total;
+
+ line_no = op->len / XDMA_CMD_AST2500_CMD_LINE_SIZE;
+ total = XDMA_CMD_AST2500_CMD_LINE_SIZE * line_no;
+ rem = (op->len - total) >>
+ XDMA_CMD_AST2500_CMD_LINE_SIZE_SHIFT;
+ line_size = XDMA_CMD_AST2500_CMD_LINE_SIZE;
+ pitch = line_size >> XDMA_CMD_AST2500_PITCH_SHIFT;
+ line_size >>= XDMA_CMD_AST2500_CMD_LINE_SIZE_SHIFT;
+
+ if (rem) {
+ u32 rbmc = bmc_addr + total;
+ struct aspeed_xdma_cmd *rcmd =
+ &(((struct aspeed_xdma_cmd *)ctx->cmdq)[nidx]);
+
+ rcmd->host_addr = op->host_addr + (u64)total;
+ rcmd->pitch = cmd_pitch |
+ ((u64)rbmc & XDMA_CMD_AST2500_PITCH_ADDR) |
+ FIELD_PREP(XDMA_CMD_AST2500_PITCH_HOST, 1) |
+ FIELD_PREP(XDMA_CMD_AST2500_PITCH_BMC, 1);
+ rcmd->cmd = cmd |
+ FIELD_PREP(XDMA_CMD_AST2500_CMD_LINE_NO, 1) |
+ FIELD_PREP(XDMA_CMD_AST2500_CMD_LINE_SIZE,
+ rem);
+
+ print_hex_dump_debug("xdma rem ", DUMP_PREFIX_OFFSET,
+ 16, 1, rcmd, sizeof(*rcmd), true);
+
+ cmd &= ~(XDMA_CMD_AST2500_CMD_IRQ_EN |
+ XDMA_CMD_AST2500_CMD_IRQ_BMC);
+
+ nidx = (nidx + 1) % XDMA_NUM_CMDS;
+ }
+ } else {
+ line_size = op->len >> XDMA_CMD_AST2500_CMD_LINE_SIZE_SHIFT;
+ }
+
+ ncmd->host_addr = op->host_addr;
+ ncmd->pitch = cmd_pitch |
+ ((u64)bmc_addr & XDMA_CMD_AST2500_PITCH_ADDR) |
+ FIELD_PREP(XDMA_CMD_AST2500_PITCH_HOST, pitch) |
+ FIELD_PREP(XDMA_CMD_AST2500_PITCH_BMC, pitch);
+ ncmd->cmd = cmd | FIELD_PREP(XDMA_CMD_AST2500_CMD_LINE_NO, line_no) |
+ FIELD_PREP(XDMA_CMD_AST2500_CMD_LINE_SIZE, line_size);
+
+ print_hex_dump_debug("xdma cmd ", DUMP_PREFIX_OFFSET, 16, 1, ncmd,
+ sizeof(*ncmd), true);
+
+ return nidx;
+}
+
+static unsigned int aspeed_xdma_ast2600_set_cmd(struct aspeed_xdma *ctx,
+ struct aspeed_xdma_op *op,
+ u32 bmc_addr)
+{
+ u64 cmd = XDMA_CMD_AST2600_CMD_IRQ_BMC |
+ (op->direction ? XDMA_CMD_AST2600_CMD_UPSTREAM : 0);
+ unsigned int line_size;
+ unsigned int nidx = (ctx->cmd_idx + 1) % XDMA_NUM_CMDS;
+ unsigned int line_no = 1;
+ unsigned int pitch = 1;
+ struct aspeed_xdma_cmd *ncmd =
+ &(((struct aspeed_xdma_cmd *)ctx->cmdq)[ctx->cmd_idx]);
+
+ if ((op->host_addr + op->len) & 0xffffffff00000000ULL)
+ cmd |= XDMA_CMD_AST2600_CMD_64_EN;
+
+ dev_dbg(ctx->dev, "xdma %s ast2600: bmc[%08x] len[%08x] "
+ "host[%016llx]\n", op->direction ? "upstream" : "downstream",
+ bmc_addr, op->len, op->host_addr);
+
+ if (op->len > XDMA_CMD_AST2600_CMD_LINE_SIZE) {
+ unsigned int rem;
+ unsigned int total;
+
+ line_no = op->len / XDMA_CMD_AST2600_CMD_MULTILINE_SIZE;
+ total = XDMA_CMD_AST2600_CMD_MULTILINE_SIZE * line_no;
+ rem = op->len - total;
+ line_size = XDMA_CMD_AST2600_CMD_MULTILINE_SIZE;
+ pitch = line_size;
+
+ if (rem) {
+ u32 rbmc = bmc_addr + total;
+ struct aspeed_xdma_cmd *rcmd =
+ &(((struct aspeed_xdma_cmd *)ctx->cmdq)[nidx]);
+
+ rcmd->host_addr = op->host_addr + (u64)total;
+ rcmd->pitch =
+ ((u64)rbmc & XDMA_CMD_AST2600_PITCH_ADDR) |
+ FIELD_PREP(XDMA_CMD_AST2600_PITCH_HOST, 1) |
+ FIELD_PREP(XDMA_CMD_AST2600_PITCH_BMC, 1);
+ rcmd->cmd = cmd |
+ FIELD_PREP(XDMA_CMD_AST2600_CMD_LINE_NO, 1) |
+ FIELD_PREP(XDMA_CMD_AST2600_CMD_LINE_SIZE,
+ rem);
+
+ print_hex_dump_debug("xdma rem ", DUMP_PREFIX_OFFSET,
+ 16, 1, rcmd, sizeof(*rcmd), true);
+
+ cmd &= ~XDMA_CMD_AST2600_CMD_IRQ_BMC;
+
+ nidx = (nidx + 1) % XDMA_NUM_CMDS;
+ }
+ } else {
+ line_size = op->len;
+ }
+
+ ncmd->host_addr = op->host_addr;
+ ncmd->pitch = ((u64)bmc_addr & XDMA_CMD_AST2600_PITCH_ADDR) |
+ FIELD_PREP(XDMA_CMD_AST2600_PITCH_HOST, pitch) |
+ FIELD_PREP(XDMA_CMD_AST2600_PITCH_BMC, pitch);
+ ncmd->cmd = cmd | FIELD_PREP(XDMA_CMD_AST2600_CMD_LINE_NO, line_no) |
+ FIELD_PREP(XDMA_CMD_AST2600_CMD_LINE_SIZE, line_size);
+
+ print_hex_dump_debug("xdma cmd ", DUMP_PREFIX_OFFSET, 16, 1, ncmd,
+ sizeof(*ncmd), true);
+
+ return nidx;
+}
+
+static void aspeed_xdma_start(struct aspeed_xdma *ctx,
+ struct aspeed_xdma_op *op, u32 bmc_addr,
+ struct aspeed_xdma_client *client)
+{
+ unsigned int nidx;
+
+ mutex_lock(&ctx->start_lock);
+
+ nidx = ctx->chip->set_cmd(ctx, op, bmc_addr);
+ memcpy(ctx->cmdq_vga_virt, ctx->cmdq, XDMA_CMDQ_SIZE);
+
+ client->in_progress = true;
+ ctx->current_client = client;
+ ctx->upstream = op->direction ? true : false;
+
+ aspeed_xdma_writel(ctx, ctx->chip->regs.bmc_cmdq_writep,
+ nidx * ctx->chip->queue_entry_size);
+
+ ctx->cmd_idx = nidx;
+
+ mutex_unlock(&ctx->start_lock);
+}
+
+static void aspeed_xdma_done(struct aspeed_xdma *ctx, bool error)
+{
+ if (ctx->current_client) {
+ ctx->current_client->error = error;
+ ctx->current_client->in_progress = false;
+ ctx->current_client = NULL;
+ }
+
+ wake_up_interruptible_all(&ctx->wait);
+}
+
+static irqreturn_t aspeed_xdma_irq(int irq, void *arg)
+{
+ struct aspeed_xdma *ctx = arg;
+ u32 status = aspeed_xdma_readl(ctx, ctx->chip->regs.status);
+
+ if (status & ctx->chip->status_bits.ds_dirty) {
+ aspeed_xdma_done(ctx, true);
+ } else {
+ if (status & ctx->chip->status_bits.us_comp) {
+ if (ctx->upstream)
+ aspeed_xdma_done(ctx, false);
+ }
+
+ if (status & ctx->chip->status_bits.ds_comp) {
+ if (!ctx->upstream)
+ aspeed_xdma_done(ctx, false);
+ }
+ }
+
+ aspeed_xdma_writel(ctx, ctx->chip->regs.status, status);
+
+ return IRQ_HANDLED;
+}
+
+static void aspeed_xdma_reset(struct aspeed_xdma *ctx)
+{
+ reset_control_assert(ctx->reset);
+ msleep(XDMA_RESET_TIME_MS);
+
+ reset_control_deassert(ctx->reset);
+ msleep(XDMA_RESET_TIME_MS);
+
+ aspeed_xdma_init_eng(ctx);
+
+ ctx->in_reset = false;
+ aspeed_xdma_done(ctx, true);
+}
+
+static void aspeed_xdma_reset_work(struct work_struct *work)
+{
+ struct aspeed_xdma *ctx = container_of(work, struct aspeed_xdma,
+ reset_work);
+
+ /*
+ * Lock to make sure operations aren't started while the engine is
+ * in reset.
+ */
+ mutex_lock(&ctx->start_lock);
+
+ aspeed_xdma_reset(ctx);
+
+ mutex_unlock(&ctx->start_lock);
+}
+
+static irqreturn_t aspeed_xdma_pcie_irq(int irq, void *arg)
+{
+ unsigned long flags;
+ struct aspeed_xdma *ctx = arg;
+
+ dev_dbg(ctx->dev, "pcie reset\n");
+
+ spin_lock_irqsave(&ctx->reset_lock, flags);
+ if (ctx->in_reset) {
+ spin_unlock_irqrestore(&ctx->reset_lock, flags);
+ return IRQ_HANDLED;
+ }
+
+ ctx->in_reset = true;
+ spin_unlock_irqrestore(&ctx->reset_lock, flags);
+
+ schedule_work(&ctx->reset_work);
+ return IRQ_HANDLED;
+}
+
+static int aspeed_xdma_probe(struct platform_device *pdev)
+{
+ int irq;
+ int pcie_irq;
+ int rc;
+ u32 vgamem[2];
+ struct regmap *scu;
+ struct regmap *sdmc;
+ struct aspeed_xdma *ctx;
+ struct device *dev = &pdev->dev;
+ const void *md = of_device_get_match_data(dev);
+
+ if (!md)
+ return -ENODEV;
+
+ ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
+ if (!ctx)
+ return -ENOMEM;
+
+ ctx->chip = md;
+ ctx->dev = dev;
+ platform_set_drvdata(pdev, ctx);
+ mutex_init(&ctx->start_lock);
+ INIT_WORK(&ctx->reset_work, aspeed_xdma_reset_work);
+ spin_lock_init(&ctx->reset_lock);
+ init_waitqueue_head(&ctx->wait);
+
+ ctx->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(ctx->base)) {
+ dev_err(dev, "Failed to map registers.\n");
+ return PTR_ERR(ctx->base);
+ }
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ dev_err(dev, "Unable to find IRQ.\n");
+ return irq;
+ }
+
+ rc = devm_request_irq(dev, irq, aspeed_xdma_irq, IRQF_SHARED,
+ DEVICE_NAME, ctx);
+ if (rc < 0) {
+ dev_err(dev, "Failed to request IRQ %d.\n", irq);
+ return rc;
+ }
+
+ ctx->clock = devm_clk_get(dev, NULL);
+ if (IS_ERR(ctx->clock)) {
+ dev_err(dev, "Failed to request clock.\n");
+ return PTR_ERR(ctx->clock);
+ }
+
+ ctx->reset = devm_reset_control_get_exclusive(dev, NULL);
+ if (IS_ERR(ctx->reset)) {
+ dev_err(dev, "Failed to request reset control.\n");
+ return PTR_ERR(ctx->reset);
+ }
+
+ ctx->cmdq = devm_kzalloc(ctx->dev, XDMA_CMDQ_SIZE, GFP_KERNEL);
+ if (!ctx->cmdq) {
+ dev_err(dev, "Failed to allocate command queue.\n");
+ return -ENOMEM;
+ }
+
+ ctx->vga_pool = devm_gen_pool_create(dev, ilog2(PAGE_SIZE), -1, NULL);
+ if (!ctx->vga_pool) {
+ dev_err(dev, "Failed to setup genalloc pool.\n");
+ return -ENOMEM;
+ }
+
+ rc = of_property_read_u32_array(dev->of_node, "vga-mem", vgamem, 2);
+ if (rc) {
+ dev_err(dev, "Unable to get VGA memory space.\n");
+ return rc;
+ }
+
+ ctx->vga_phys = vgamem[0];
+ ctx->vga_size = vgamem[1];
+
+ ctx->vga_virt = devm_ioremap(dev, ctx->vga_phys, ctx->vga_size);
+ if (IS_ERR(ctx->vga_virt)) {
+ dev_err(dev, "Failed to map VGA memory space.\n");
+ return PTR_ERR(ctx->vga_virt);
+ }
+
+ rc = gen_pool_add_virt(ctx->vga_pool, (unsigned long)ctx->vga_virt,
+ ctx->vga_phys, ctx->vga_size, -1);
+ if (rc) {
+ dev_err(ctx->dev, "Failed to add memory to genalloc pool.\n");
+ return rc;
+ }
+
+ sdmc = syscon_regmap_lookup_by_phandle(dev->of_node, "sdmc");
+ if (IS_ERR(sdmc)) {
+ dev_err(dev, "Unable to configure memory controller.\n");
+ return PTR_ERR(sdmc);
+ }
+
+ regmap_update_bits(sdmc, SDMC_REMAP, ctx->chip->sdmc_remap,
+ ctx->chip->sdmc_remap);
+
+ scu = syscon_regmap_lookup_by_phandle(dev->of_node, "scu");
+ if (!IS_ERR(scu)) {
+ u32 selection;
+ bool pcie_device_bmc = true;
+ const u32 bmc = SCU_PCIE_CONF_BMC_EN |
+ SCU_PCIE_CONF_BMC_EN_MSI | SCU_PCIE_CONF_BMC_EN_IRQ |
+ SCU_PCIE_CONF_BMC_EN_DMA;
+ const u32 vga = SCU_PCIE_CONF_VGA_EN |
+ SCU_PCIE_CONF_VGA_EN_MSI | SCU_PCIE_CONF_VGA_EN_IRQ |
+ SCU_PCIE_CONF_VGA_EN_DMA;
+ const char *pcie = NULL;
+
+ if (!of_property_read_string(dev->of_node, "pcie-device",
+ &pcie)) {
+ if (!strcmp(pcie, "vga"))
+ pcie_device_bmc = false;
+ }
+
+ if (pcie_device_bmc) {
+ selection = bmc;
+ regmap_write(scu, ctx->chip->scu_bmc_class,
+ SCU_BMC_CLASS_REV_XDMA);
+ } else {
+ selection = vga;
+ }
+
+ regmap_update_bits(scu, ctx->chip->scu_pcie_conf, bmc | vga,
+ selection);
+ } else {
+ dev_warn(dev, "Unable to configure PCIe; continuing.\n");
+ }
+
+ rc = clk_prepare_enable(ctx->clock);
+ if (rc) {
+ dev_err(dev, "Failed to enable the clock.\n");
+ return rc;
+ }
+ msleep(XDMA_RESET_TIME_MS);
+
+ rc = reset_control_deassert(ctx->reset);
+ if (rc) {
+ clk_disable_unprepare(ctx->clock);
+
+ dev_err(dev, "Failed to clear the reset.\n");
+ return rc;
+ }
+ msleep(XDMA_RESET_TIME_MS);
+
+ ctx->cmdq_vga_virt = gen_pool_dma_alloc(ctx->vga_pool, XDMA_CMDQ_SIZE,
+ &ctx->cmdq_vga_phys);
+ if (!ctx->cmdq_vga_virt) {
+ dev_err(ctx->dev, "Failed to genalloc cmdq.\n");
+
+ reset_control_assert(ctx->reset);
+ clk_disable_unprepare(ctx->clock);
+ return -ENOMEM;
+ }
+
+ aspeed_xdma_init_eng(ctx);
+
+ /*
+ * This interrupt could fire immediately so only request it once the
+ * engine and driver are initialized.
+ */
+ pcie_irq = platform_get_irq(pdev, 1);
+ if (pcie_irq < 0) {
+ dev_warn(dev, "Unable to find PCI-E IRQ.\n");
+ } else {
+ rc = devm_request_irq(dev, pcie_irq, aspeed_xdma_pcie_irq,
+ IRQF_SHARED, DEVICE_NAME, ctx);
+ if (rc < 0)
+ dev_warn(dev, "Failed to request PCI-E IRQ %d.\n", rc);
+ }
+
+ return 0;
+}
+
+static int aspeed_xdma_remove(struct platform_device *pdev)
+{
+ struct aspeed_xdma *ctx = platform_get_drvdata(pdev);
+
+ gen_pool_free(ctx->vga_pool, (unsigned long)ctx->cmdq_vga_virt,
+ XDMA_CMDQ_SIZE);
+
+ reset_control_assert(ctx->reset);
+ clk_disable_unprepare(ctx->clock);
+
+ return 0;
+}
+
+static const struct aspeed_xdma_chip aspeed_ast2500_xdma_chip = {
+ .control = XDMA_AST2500_CTRL_US_COMP | XDMA_AST2500_CTRL_DS_COMP |
+ XDMA_AST2500_CTRL_DS_DIRTY | XDMA_AST2500_CTRL_DS_SIZE_256 |
+ XDMA_AST2500_CTRL_DS_TIMEOUT | XDMA_AST2500_CTRL_DS_CHECK_ID,
+ .scu_bmc_class = SCU_AST2500_BMC_CLASS_REV,
+ .scu_pcie_conf = SCU_AST2500_PCIE_CONF,
+ .sdmc_remap = SDMC_AST2500_REMAP_PCIE | SDMC_AST2500_REMAP_XDMA,
+ .queue_entry_size = XDMA_AST2500_QUEUE_ENTRY_SIZE,
+ .regs = {
+ .bmc_cmdq_addr = XDMA_AST2500_BMC_CMDQ_ADDR,
+ .bmc_cmdq_endp = XDMA_AST2500_BMC_CMDQ_ENDP,
+ .bmc_cmdq_writep = XDMA_AST2500_BMC_CMDQ_WRITEP,
+ .bmc_cmdq_readp = XDMA_AST2500_BMC_CMDQ_READP,
+ .control = XDMA_AST2500_CTRL,
+ .status = XDMA_AST2500_STATUS,
+ },
+ .status_bits = {
+ .us_comp = XDMA_AST2500_STATUS_US_COMP,
+ .ds_comp = XDMA_AST2500_STATUS_DS_COMP,
+ .ds_dirty = XDMA_AST2500_STATUS_DS_DIRTY,
+ },
+ .set_cmd = aspeed_xdma_ast2500_set_cmd,
+};
+
+static const struct aspeed_xdma_chip aspeed_ast2600_xdma_chip = {
+ .control = XDMA_AST2600_CTRL_US_COMP | XDMA_AST2600_CTRL_DS_COMP |
+ XDMA_AST2600_CTRL_DS_DIRTY | XDMA_AST2600_CTRL_DS_SIZE_256,
+ .scu_bmc_class = SCU_AST2600_BMC_CLASS_REV,
+ .scu_pcie_conf = SCU_AST2600_PCIE_CONF,
+ .sdmc_remap = SDMC_AST2600_REMAP_XDMA,
+ .queue_entry_size = XDMA_AST2600_QUEUE_ENTRY_SIZE,
+ .regs = {
+ .bmc_cmdq_addr = XDMA_AST2600_BMC_CMDQ_ADDR,
+ .bmc_cmdq_endp = XDMA_AST2600_BMC_CMDQ_ENDP,
+ .bmc_cmdq_writep = XDMA_AST2600_BMC_CMDQ_WRITEP,
+ .bmc_cmdq_readp = XDMA_AST2600_BMC_CMDQ_READP,
+ .control = XDMA_AST2600_CTRL,
+ .status = XDMA_AST2600_STATUS,
+ },
+ .status_bits = {
+ .us_comp = XDMA_AST2600_STATUS_US_COMP,
+ .ds_comp = XDMA_AST2600_STATUS_DS_COMP,
+ .ds_dirty = XDMA_AST2600_STATUS_DS_DIRTY,
+ },
+ .set_cmd = aspeed_xdma_ast2600_set_cmd,
+};
+
+static const struct of_device_id aspeed_xdma_match[] = {
+ {
+ .compatible = "aspeed,ast2500-xdma",
+ .data = &aspeed_ast2500_xdma_chip,
+ },
+ {
+ .compatible = "aspeed,ast2600-xdma",
+ .data = &aspeed_ast2600_xdma_chip,
+ },
+ { },
+};
+
+static struct platform_driver aspeed_xdma_driver = {
+ .probe = aspeed_xdma_probe,
+ .remove = aspeed_xdma_remove,
+ .driver = {
+ .name = DEVICE_NAME,
+ .of_match_table = aspeed_xdma_match,
+ },
+};
+
+module_platform_driver(aspeed_xdma_driver);
+
+MODULE_AUTHOR("Eddie James");
+MODULE_DESCRIPTION("Aspeed XDMA Engine Driver");
+MODULE_LICENSE("GPL v2");
diff --git a/include/uapi/linux/aspeed-xdma.h b/include/uapi/linux/aspeed-xdma.h
new file mode 100644
index 0000000..f39f38e
--- /dev/null
+++ b/include/uapi/linux/aspeed-xdma.h
@@ -0,0 +1,41 @@
+/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
+/* Copyright IBM Corp 2019 */
+
+#ifndef _UAPI_LINUX_ASPEED_XDMA_H_
+#define _UAPI_LINUX_ASPEED_XDMA_H_
+
+#include <linux/types.h>
+
+/*
+ * aspeed_xdma_direction
+ *
+ * ASPEED_XDMA_DIRECTION_DOWNSTREAM: transfers data from the host to the BMC
+ *
+ * ASPEED_XDMA_DIRECTION_UPSTREAM: transfers data from the BMC to the host
+ *
+ * ASPEED_XDMA_DIRECTION_RESET: resets the XDMA engine
+ */
+enum aspeed_xdma_direction {
+ ASPEED_XDMA_DIRECTION_DOWNSTREAM = 0,
+ ASPEED_XDMA_DIRECTION_UPSTREAM,
+ ASPEED_XDMA_DIRECTION_RESET,
+};
+
+/*
+ * aspeed_xdma_op
+ *
+ * host_addr: the DMA address on the host side, typically configured by PCI
+ * subsystem
+ *
+ * len: the size of the transfer in bytes
+ *
+ * direction: an enumerator indicating the direction of the DMA operation; see
+ * enum aspeed_xdma_direction
+ */
+struct aspeed_xdma_op {
+ __u64 host_addr;
+ __u32 len;
+ __u32 direction;
+};
+
+#endif /* _UAPI_LINUX_ASPEED_XDMA_H_ */
--
1.8.3.1