Hi, Lee
在 2025/4/5 上午12:06, Lee Jones 写道:
On Thu, 03 Apr 2025, Qunqin Zhao wrote:
This driver supports Loongson Security Module, which provides the control
for it's hardware encryption acceleration child devices.
Co-developed-by: Yinggang Gu <guyingg...@loongson.cn>
Signed-off-by: Yinggang Gu <guyingg...@loongson.cn>
Signed-off-by: Qunqin Zhao <zhaoqun...@loongson.cn>
Reviewed-by: Huacai Chen <chenhua...@loongson.cn>
---
v7: Moved Kconfig entry between MFD_INTEL_M10_BMC_PMCI and MFD_QNAP_MCU.
Renamed se_enable_int_locked() to se_enable_int(), then moved the
lock out of se_disable_int().
"se_send_genl_cmd" ---> "se_send_cmd".
"struct lsse_ch" ---> "struct se_channel".
v6: Replace all "ls6000se" with "loongson"
v5: Registered "ls6000se-rng" device.
v3-v4: None
v2: Removed "ls6000se-sdf" device, added "ls6000se-tpm" device.
Passed dmamem size to SE firmware in se_init_hw() function.
drivers/mfd/Kconfig | 10 +
drivers/mfd/Makefile | 2 +
drivers/mfd/loongson-se.c | 374 ++++++++++++++++++++++++++++++++
include/linux/mfd/loongson-se.h | 75 +++++++
4 files changed, 461 insertions(+)
create mode 100644 drivers/mfd/loongson-se.c
create mode 100644 include/linux/mfd/loongson-se.h
...
diff --git a/drivers/mfd/loongson-se.c b/drivers/mfd/loongson-se.c
new file mode 100644
index 000000000..4f30695de
--- /dev/null
+++ b/drivers/mfd/loongson-se.c
@@ -0,0 +1,374 @@
+// SPDX-License-Identifier: GPL-2.0+
+/* Copyright (C) 2025 Loongson Technology Corporation Limited */
+
+#include <linux/acpi.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/loongson-se.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+
+/*
+ * The Loongson Security Module provides the control for hardware
+ * encryption acceleration child devices. The SE framework is
+ * shown as follows:
+ *
+ * +------------+
+ * | CPU |
+ * +------------+
+ * ^ ^
+ * DMA | | IRQ
+ * v v
+ * +-----------------------------------+
+ * | Loongson Security Module |
+ * +-----------------------------------+
+ * ^ ^
+ * channel1 | channel2 |
+ * v v
+ * +-----------+ +----------+
+ * | sub-dev1 | | sub-dev2 | ..... Max sub-dev31
+ * +-----------+ +----------+
+ *
+ * The CPU cannot directly communicate with SE's sub devices,
+ * but sends commands to SE, which processes the commands and
+ * sends them to the corresponding sub devices.
+ */
+
+struct loongson_se {
+ void __iomem *base;
+ u32 version;
+ spinlock_t dev_lock;
+ struct completion cmd_completion;
+
+ /* dma memory */
+ void *mem_base;
+ int mem_map_pages;
+ unsigned long *mem_map;
+
+ /* channel */
+ struct mutex ch_init_lock;
+ struct se_channel chs[SE_CH_MAX];
+};
+
+union se_request {
+ u32 info[8];
+ struct se_cmd {
+ u32 cmd;
+ u32 info[7];
+ } req;
+ struct se_res {
+ u32 cmd;
+ u32 cmd_ret;
+ u32 info[6];
+ } res;
+};
+
+static inline u32 se_readl(struct loongson_se *se, u32 off)
+{
+ return readl(se->base + off);
+}
+
+static inline void se_writel(struct loongson_se *se, u32 val, u32 off)
+{
+ writel(val, se->base + off);
+}
Why are these being abstracted? Just use readl/writel directly.
Ok
+static void se_enable_int(struct loongson_se *se, u32 int_bit)
+{
+ u32 tmp;
+
+ tmp = se_readl(se, SE_S2LINT_EN);
+ tmp |= int_bit;
+ se_writel(se, tmp, SE_S2LINT_EN);
+}
+
+static void se_disable_int(struct loongson_se *se, u32 int_bit)
+{
+ u32 tmp;
+
+ tmp = se_readl(se, SE_S2LINT_EN);
+ tmp &= ~(int_bit);
+ se_writel(se, tmp, SE_S2LINT_EN);
+}
+
+static int se_poll(struct loongson_se *se, u32 int_bit)
+{
+ u32 status;
+ int err;
+
+ spin_lock_irq(&se->dev_lock);
+
+ se_enable_int(se, int_bit);
+ se_writel(se, int_bit, SE_L2SINT_SET);
+ err = readl_relaxed_poll_timeout_atomic(se->base + SE_L2SINT_STAT,
status,
+ !(status & int_bit), 1, 10000);
+
+ spin_unlock_irq(&se->dev_lock);
+
+ return err;
+}
+
+static int se_send_requeset(struct loongson_se *se, union se_request *req)
What's a requeset?
Request looks confusing, would it be better to call it a command package?
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(req->info); i++)
+ se_writel(se, req->info[i], SE_DATA_S + i * 4);
+
+ return se_poll(se, SE_INT_SETUP);
+}
+
+/*
+ * Called by SE's child device driver.
+ * Send a request to the corresponding device.
+ */
+int se_send_ch_requeset(struct se_channel *ch)
+{
+ return se_poll(ch->se, ch->int_bit);
+}
More pointless abstraction. Just export se_poll()?
Ok
+EXPORT_SYMBOL_GPL(se_send_ch_requeset);
+
+static int se_get_res(struct loongson_se *se, u32 cmd, union se_request *res)
What are we getting here? What is a 'res'?
Response package from the device.
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(res->info); i++)
for (int i = 0; ...
OK
+ res->info[i] = se_readl(se, SE_DATA_L + i * 4);
+
+ if (res->res.cmd != cmd)
+ return -EFAULT;
+
+ return 0;
+}
+
+static int se_send_cmd(struct loongson_se *se, union se_request *req)
+{
+ int err;
+
+ err = se_send_requeset(se, req);
+ if (err)
+ return err;
+
+ if (!wait_for_completion_timeout(&se->cmd_completion, HZ))
+ return -ETIME;
-ETIMEDOUT
OK
+
+ return se_get_res(se, req->req.cmd, req);
+}
+
+static int se_set_msg(struct se_channel *ch)
+{
+ struct loongson_se *se = ch->se;
+ union se_request req;
+
+ req.req.cmd = SE_CMD_SETMSG;
+ req.req.info[0] = ch->id;
+ req.req.info[1] = ch->smsg - se->mem_base;
+ req.req.info[2] = ch->msg_size;
+
+ return se_send_cmd(se, &req);
+}
+
+static irqreturn_t se_irq(int irq, void *dev_id)
se_irq_handler()
OK
+{
+ struct loongson_se *se = (struct loongson_se *)dev_id;
+ struct se_channel *ch;
+ unsigned long flag;
+ u32 int_status;
+ int id;
+
+ int_status = se_readl(se, SE_S2LINT_STAT);
+
+ spin_lock_irqsave(&se->dev_lock, flag);
+ se_disable_int(se, int_status);
+ spin_unlock_irqrestore(&se->dev_lock, flag);
+
+ if (int_status & SE_INT_SETUP) {
+ complete(&se->cmd_completion);
+ int_status &= ~SE_INT_SETUP;
+ se_writel(se, SE_INT_SETUP, SE_S2LINT_CL);
+ }
+
+ while (int_status) {
+ id = __ffs(int_status);
+
+ ch = &se->chs[id];
+ if (ch->complete)
+ ch->complete(ch);
+ int_status &= ~BIT(id);
+ se_writel(se, BIT(id), SE_S2LINT_CL);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static int se_init_hw(struct loongson_se *se, dma_addr_t addr, int size)
+{
+ union se_request req;
+ int err;
+
+ /* Start engine */
+ req.req.cmd = SE_CMD_START;
+ err = se_send_cmd(se, &req);
+ if (err)
+ return err;
+
+ /* Get Version */
+ req.req.cmd = SE_CMD_GETVER;
+ err = se_send_cmd(se, &req);
+ if (err)
+ return err;
+ se->version = req.res.info[0];
+
+ /* Setup dma memory */
DMA
OK
+ req.req.cmd = SE_CMD_SETBUF;
+ req.req.info[0] = addr & 0xffffffff;
+ req.req.info[1] = addr >> 32;
Define these magic numbers please.
OK
+ req.req.info[2] = size;
+
+ return se_send_cmd(se, &req);
+}
+
+/*
+ * se_init_ch() - Init the channel used by child device.
+ *
+ * Allocate dma memory as agreed upon with SE on SE probe,
DMA, throughout please.
OK
+ * and register the callback function when the data processing
+ * in this channel is completed.
+ */
+struct se_channel *se_init_ch(struct device *dev, int id, int data_size, int
msg_size,
What's a "ch"?
Channel. Sorry for this confusing abbreviation.
+ void *priv, void (*complete)(struct se_channel
*se_ch))
I'm not entirely sure what this device is or how it works, but this
isn't really what MFD is for. MFD has no knowledge of channel
initialisation or completion call-backs or the like. What you have here
goes beyond scope.
DMA memory used by different sub devices should better be contiguous in
physical addresses,
so a large block of DMA memory needs to be allocated first in probe
function,
and then each sub device allocates a small block from this large block
of DMA memory during channel initialization.
This is why i need a channel initialization function.
+{
+ struct loongson_se *se = dev_get_drvdata(dev);
+ struct se_channel *ch;
+ int data_first, data_nr;
+ int msg_first, msg_nr;
+
+ mutex_lock(&se->ch_init_lock);
+
+ ch = &se->chs[id];
+ ch->se = se;
+ ch->id = id;
+ ch->int_bit = BIT(id);
This can be derived from ch->id, so you don't need to store it.
Or you don't need 'id' - one of the two.
Will fix.
+
+ data_nr = round_up(data_size, PAGE_SIZE) / PAGE_SIZE;
+ data_first = bitmap_find_next_zero_area(se->mem_map, se->mem_map_pages,
+ 0, data_nr, 0);
+ if (data_first >= se->mem_map_pages) {
+ ch = NULL;
+ goto out_unlock;
+ }
+
+ bitmap_set(se->mem_map, data_first, data_nr);
+ ch->off = data_first * PAGE_SIZE;
+ ch->data_buffer = se->mem_base + ch->off;
+ ch->data_size = data_size;
+
+ msg_nr = round_up(msg_size, PAGE_SIZE) / PAGE_SIZE;
+ msg_first = bitmap_find_next_zero_area(se->mem_map, se->mem_map_pages,
+ 0, msg_nr, 0);
+ if (msg_first >= se->mem_map_pages) {
+ ch = NULL;
+ goto out_unlock;
+ }
+
+ bitmap_set(se->mem_map, msg_first, msg_nr);
+ ch->smsg = se->mem_base + msg_first * PAGE_SIZE;
+ ch->rmsg = ch->smsg + msg_size / 2;
+ ch->msg_size = msg_size;
+ ch->complete = complete;
+ ch->priv = priv;
+ ch->version = se->version;
+
+ if (se_set_msg(ch))
+ ch = NULL;
+
+out_unlock:
+ mutex_unlock(&se->ch_init_lock);
+
+ return ch;
+}
+EXPORT_SYMBOL_GPL(se_init_ch);
+
+static const struct mfd_cell se_devs[] = {
+ { .name = "loongson-rng" },
+ { .name = "loongson-tpm" },
+};
+
+static int loongson_se_probe(struct platform_device *pdev)
This function is totally unreadable. I'm not even going to try, sorry.
This function is mainly responsible for allocating a DMA memory for all
sub devices and registering interrupt handling functions.
+{
+ struct loongson_se *se;
+ struct device *dev = &pdev->dev;
+ int nr_irq, irq, err, size;
+ dma_addr_t paddr;
+
+ se = devm_kmalloc(dev, sizeof(*se), GFP_KERNEL);
+ if (!se)
+ return -ENOMEM;
+ dev_set_drvdata(dev, se);
+ init_completion(&se->cmd_completion);
+ spin_lock_init(&se->dev_lock);
+ mutex_init(&se->ch_init_lock);
+ dma_set_mask_and_coherent(dev, DMA_BIT_MASK(64));
+ if (device_property_read_u32(dev, "dmam_size", &size))
+ return -ENODEV;
+ size = roundup_pow_of_two(size);
+ se->mem_base = dmam_alloc_coherent(dev, size, &paddr, GFP_KERNEL);
+ if (!se->mem_base)
+ return -ENOMEM;
+ se->mem_map_pages = size / PAGE_SIZE;
+ se->mem_map = devm_bitmap_zalloc(dev, se->mem_map_pages, GFP_KERNEL);
+ if (!se->mem_map)
+ return -ENOMEM;
+
+ se->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(se->base))
+ return PTR_ERR(se->base);
+
+ nr_irq = platform_irq_count(pdev);
+ if (nr_irq <= 0)
+ return -ENODEV;
+ while (nr_irq) {
+ irq = platform_get_irq(pdev, --nr_irq);
+ /* Use the same interrupt handler address.
+ * Determine which irq it is accroding
+ * SE_S2LINT_STAT register.
+ */
+ err = devm_request_irq(dev, irq, se_irq, 0, "loongson-se", se);
+ if (err)
+ dev_err(dev, "failed to request irq: %d\n", irq);
+ }
+
+ err = se_init_hw(se, paddr, size);
+ if (err)
+ return err;
+
+ return devm_mfd_add_devices(dev, 0, se_devs, ARRAY_SIZE(se_devs),
+ NULL, 0, NULL);
+}
+
+static const struct acpi_device_id loongson_se_acpi_match[] = {
+ {"LOON0011", 0},
Spaces near the {}s
OK
+ {}
+};
+MODULE_DEVICE_TABLE(acpi, loongson_se_acpi_match);
+
+static struct platform_driver loongson_se_driver = {
+ .probe = loongson_se_probe,
+ .driver = {
+ .name = "loongson-se",
+ .acpi_match_table = loongson_se_acpi_match,
+ },
+};
+module_platform_driver(loongson_se_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Yinggang Gu <guyingg...@loongson.cn>");
+MODULE_AUTHOR("Qunqin Zhao <zhaoqun...@loongson.cn>");
+MODULE_DESCRIPTION("Loongson Security Module driver");
diff --git a/include/linux/mfd/loongson-se.h b/include/linux/mfd/loongson-se.h
new file mode 100644
index 000000000..f209b7043
--- /dev/null
+++ b/include/linux/mfd/loongson-se.h
@@ -0,0 +1,75 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/* Copyright (C) 2025 Loongson Technology Corporation Limited */
+
+#ifndef __LOONGSON_SE_H__
+#define __LOONGSON_SE_H__
+
+#define SE_DATA_S 0x0
+#define SE_DATA_L 0x20
+#define SE_S2LINT_STAT 0x88
+#define SE_S2LINT_EN 0x8c
+#define SE_S2LINT_SET 0x90
+#define SE_S2LINT_CL 0x94
+#define SE_L2SINT_STAT 0x98
+#define SE_L2SINT_EN 0x9c
+#define SE_L2SINT_SET 0xa0
+#define SE_L2SINT_CL 0xa4
+
+/* INT bit definition */
+#define SE_INT_SETUP BIT(0)
+#define SE_INT_TPM BIT(5)
+
+#define SE_CMD_START 0x0
+#define SE_CMD_STOP 0x1
+#define SE_CMD_GETVER 0x2
+#define SE_CMD_SETBUF 0x3
+#define SE_CMD_SETMSG 0x4
+
+#define SE_CMD_RNG 0x100
+#define SE_CMD_SM2_SIGN 0x200
+#define SE_CMD_SM2_VSIGN 0x201
+#define SE_CMD_SM3_DIGEST 0x300
+#define SE_CMD_SM3_UPDATE 0x301
+#define SE_CMD_SM3_FINISH 0x302
+#define SE_CMD_SM4_ECB_ENCRY 0x400
+#define SE_CMD_SM4_ECB_DECRY 0x401
+#define SE_CMD_SM4_CBC_ENCRY 0x402
+#define SE_CMD_SM4_CBC_DECRY 0x403
+#define SE_CMD_SM4_CTR 0x404
+#define SE_CMD_TPM 0x500
+#define SE_CMD_ZUC_INIT_READ 0x600
+#define SE_CMD_ZUC_READ 0x601
+#define SE_CMD_SDF 0x700
+
+#define SE_CH_MAX 32
+#define SE_CH_RNG 1
+#define SE_CH_SM2 2
+#define SE_CH_SM3 3
+#define SE_CH_SM4 4
+#define SE_CH_TPM 5
+#define SE_CH_ZUC 6
+#define SE_CH_SDF 7
+
+struct se_channel {
+ struct loongson_se *se;
+ void *priv;
+ u32 version;
What do you do with this information?
Will remove it.
+ u32 id;
+ u32 int_bit;
+
+ void *smsg;
+ void *rmsg;
+ int msg_size;
+
+ void *data_buffer;
+ int data_size;
+ u32 off;
Most of these variables have terrible names.
So either use proper nomenclature or document them.
OK.
+
+ void (*complete)(struct se_channel *se_ch);
Non-subsystem-level call-backs are generally evil.
You'd need to provide a very good reason as to why nothing else works.
How about remove the callback, but define a "struct completion" in
struct se_channel?
Thanks for your comments.
BR, Qunqin.
+};
+
+struct se_channel *se_init_ch(struct device *dev, int id, int data_size, int
msg_size,
+ void *priv, void (*complete)(struct se_channel
*se_ch));
+int se_send_ch_requeset(struct se_channel *ch);
+
+#endif
--
2.45.2
