Re: [patch v14 2/4] drivers: jtag: Add Aspeed SoC 24xx and 25xx families JTAG master driver

From: Joel Stanley
Date: Thu Dec 14 2017 - 20:35:00 EST

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On Fri, Dec 15, 2017 at 2:59 AM, Oleksandr Shamray
<oleksandrs@xxxxxxxxxxxx> wrote:
> Driver adds support of Aspeed 2500/2400 series SOC JTAG master controller.

Looks good. I have a few small things below, but I am happy to see
this merged from my point of view as ASPEED maintainer.

Cheers,

Joel

> +
> +menuconfig JTAG_ASPEED
> + tristate "Aspeed SoC JTAG controller support"
> + depends on JTAG && HAS_IOMEM

Add ARCH_ASPEED || COMPILE_TEST

> + ---help---
> + This provides a support for Aspeed JTAG device, equipped on
> + Aspeed SoC 24xx and 25xx families. Drivers allows programming
> + of hardware devices, connected to SoC through the JTAG interface.
> +
> + If you want this support, you should say Y here.
> +
> + To compile this driver as a module, choose M here: the module will
> + be called jtag-aspeed.
> diff --git a/drivers/jtag/Makefile b/drivers/jtag/Makefile
> index af37493..04a855e 100644
> --- a/drivers/jtag/Makefile
> +++ b/drivers/jtag/Makefile
> @@ -1 +1,2 @@
> obj-$(CONFIG_JTAG) += jtag.o
> +obj-$(CONFIG_JTAG_ASPEED) += jtag-aspeed.o
> diff --git a/drivers/jtag/jtag-aspeed.c b/drivers/jtag/jtag-aspeed.c
> new file mode 100644
> index 0000000..99277d2
> --- /dev/null
> +++ b/drivers/jtag/jtag-aspeed.c
> @@ -0,0 +1,783 @@

> +static int aspeed_jtag_xfer(struct jtag *jtag, struct jtag_xfer *xfer,
> + u8 *xfer_data)
> +{
> + static const u8 sm_update_shiftir[] = {1, 1, 0, 0};
> + static const u8 sm_update_shiftdr[] = {1, 0, 0};
> + static const u8 sm_pause_idle[] = {1, 1, 0};
> + static const u8 sm_pause_update[] = {1, 1};
> + struct aspeed_jtag *aspeed_jtag = jtag_priv(jtag);
> + unsigned long *data = (unsigned long *)xfer_data;
> + unsigned long remain_xfer = xfer->length;
> + unsigned long offset;
> + char dbg_str[256];
> + int pos = 0;
> + int i;
> +
> + for (offset = 0, i = 0; offset < xfer->length;
> + offset += ASPEED_JTAG_DATA_CHUNK_SIZE, i++) {

It looks like offset is unused.

> + pos += snprintf(&dbg_str[pos], sizeof(dbg_str) - pos,
> + "0x%08lx ", data[i]);
> + }
> +
> + dev_dbg(aspeed_jtag->dev, "aspeed_jtag %s %s xfer, mode:%s, END:%d, len:%lu, TDI[%s]\n",
> + xfer->type == JTAG_SIR_XFER ? "SIR" : "SDR",
> + xfer->direction == JTAG_READ_XFER ? "READ" : "WRITE",
> + aspeed_jtag->mode & JTAG_XFER_HW_MODE ? "HW" : "SW",
> + xfer->endstate, remain_xfer, dbg_str);
> +
> + if (!(aspeed_jtag->mode & JTAG_XFER_HW_MODE)) {
> + /* SW mode */
> + aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_SW_MODE_EN |
> + ASPEED_JTAG_SW_MODE_TDIO, ASPEED_JTAG_SW);
> +
> + if (aspeed_jtag->status != JTAG_STATE_IDLE) {
> + /*IR/DR Pause->Exit2 IR / DR->Update IR /DR */
> + aspeed_jtag_sm_cycle(aspeed_jtag, sm_pause_update,
> + sizeof(sm_pause_update));
> + }
> +
> + if (xfer->type == JTAG_SIR_XFER)
> + /* ->IRSCan->CapIR->ShiftIR */
> + aspeed_jtag_sm_cycle(aspeed_jtag, sm_update_shiftir,
> + sizeof(sm_update_shiftir));
> + else
> + /* ->DRScan->DRCap->DRShift */
> + aspeed_jtag_sm_cycle(aspeed_jtag, sm_update_shiftdr,
> + sizeof(sm_update_shiftdr));
> +
> + aspeed_jtag_xfer_sw(aspeed_jtag, xfer, data);
> +
> + /* DIPause/DRPause */
> + aspeed_jtag_tck_cycle(aspeed_jtag, 0, 0);
> +
> + if (xfer->endstate == JTAG_STATE_IDLE) {
> + /* ->DRExit2->DRUpdate->IDLE */
> + aspeed_jtag_sm_cycle(aspeed_jtag, sm_pause_idle,
> + sizeof(sm_pause_idle));
> + }
> + } else {
> + /* hw mode */
> + aspeed_jtag_write(aspeed_jtag, 0, ASPEED_JTAG_SW);
> + aspeed_jtag_xfer_hw(aspeed_jtag, xfer, data);
> + }
> +
> + aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_SW_MODE_EN |
> + ASPEED_JTAG_SW_MODE_TDIO, ASPEED_JTAG_SW);
> + aspeed_jtag->status = xfer->endstate;
> + return 0;
> +}
>
> +
> +static irqreturn_t aspeed_jtag_interrupt(s32 this_irq, void *dev_id)
> +{
> + struct aspeed_jtag *aspeed_jtag = dev_id;
> + irqreturn_t ret;
> + u32 status;
> +
> + status = aspeed_jtag_read(aspeed_jtag, ASPEED_JTAG_ISR);
> + dev_dbg(aspeed_jtag->dev, "status %x\n", status);
> +
> + if (status & ASPEED_JTAG_ISR_INT_MASK) {
> + aspeed_jtag_write(aspeed_jtag,
> + (status & ASPEED_JTAG_ISR_INT_MASK)
> + | (status & ASPEED_JTAG_ISR_INT_EN_MASK),
> + ASPEED_JTAG_ISR);
> + aspeed_jtag->flag |= status & ASPEED_JTAG_ISR_INT_MASK;
> + }
> +
> + if (aspeed_jtag->flag) {
> + wake_up_interruptible(&aspeed_jtag->jtag_wq);
> + ret = IRQ_HANDLED;
> + } else {
> + dev_err(aspeed_jtag->dev, "aspeed_jtag irq status:%x\n",

using dev_err will give you sensible prefixes for any messages that
print out. You could remove "aspeed_jtag" from this any any other
prints you have.

> + status);
> + ret = IRQ_NONE;
> + }
> + return ret;
> +}
> +
> +int aspeed_jtag_init(struct platform_device *pdev,
> + struct aspeed_jtag *aspeed_jtag)
> +{
> + struct resource *res;
> + int err;
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + aspeed_jtag->reg_base = devm_ioremap_resource(aspeed_jtag->dev, res);
> + if (IS_ERR(aspeed_jtag->reg_base))
> + return -ENOMEM;
> +
> + aspeed_jtag->pclk = devm_clk_get(aspeed_jtag->dev, NULL);
> + if (IS_ERR(aspeed_jtag->pclk)) {
> + dev_err(aspeed_jtag->dev, "devm_clk_get failed\n");
> + return PTR_ERR(aspeed_jtag->pclk);
> + }
> +
> + clk_prepare_enable(aspeed_jtag->pclk);

Can you move this below the platform_get_irq? that way you can return
an error if the getting the IRQ fails, without having to clean up the
clock.

> +
> + aspeed_jtag->irq = platform_get_irq(pdev, 0);
> + if (aspeed_jtag->irq < 0) {
> + dev_err(aspeed_jtag->dev, "no irq specified\n");
> + err = -ENOENT;
> + goto clk_unprep;
> + }
> +
> + /* Enable clock */
> + aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_CTL_ENG_EN |
> + ASPEED_JTAG_CTL_ENG_OUT_EN, ASPEED_JTAG_CTRL);
> + aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_SW_MODE_EN |
> + ASPEED_JTAG_SW_MODE_TDIO, ASPEED_JTAG_SW);
> +
> + err = devm_request_irq(aspeed_jtag->dev, aspeed_jtag->irq,
> + aspeed_jtag_interrupt, 0,
> + "aspeed-jtag", aspeed_jtag);
> + if (err) {
> + dev_err(aspeed_jtag->dev, "aspeed_jtag unable to get IRQ");
> + goto clk_unprep;
> + }
> + dev_dbg(&pdev->dev, "aspeed_jtag:IRQ %d.\n", aspeed_jtag->irq);

Again, remove the aspeed_jtag prefix.

> +
> + aspeed_jtag_write(aspeed_jtag, ASPEED_JTAG_ISR_INST_PAUSE |
> + ASPEED_JTAG_ISR_INST_COMPLETE |
> + ASPEED_JTAG_ISR_DATA_PAUSE |
> + ASPEED_JTAG_ISR_DATA_COMPLETE |
> + ASPEED_JTAG_ISR_INST_PAUSE_EN |
> + ASPEED_JTAG_ISR_INST_COMPLETE_EN |
> + ASPEED_JTAG_ISR_DATA_PAUSE_EN |
> + ASPEED_JTAG_ISR_DATA_COMPLETE_EN,
> + ASPEED_JTAG_ISR);
> +
> + aspeed_jtag->flag = 0;
> + aspeed_jtag->mode = 0;
> + init_waitqueue_head(&aspeed_jtag->jtag_wq);
> + return 0;
> +
> +clk_unprep:
> + clk_disable_unprepare(aspeed_jtag->pclk);
> + return err;
> +}
> +
> +int aspeed_jtag_deinit(struct platform_device *pdev,
> + struct aspeed_jtag *aspeed_jtag)
> +{
> + aspeed_jtag_write(aspeed_jtag, 0, ASPEED_JTAG_ISR);
> + /* Disable clock */
> + aspeed_jtag_write(aspeed_jtag, 0, ASPEED_JTAG_CTRL);
> + clk_disable_unprepare(aspeed_jtag->pclk);
> + return 0;
> +}
> +
> +static const struct jtag_ops aspeed_jtag_ops = {
> + .freq_get = aspeed_jtag_freq_get,
> + .freq_set = aspeed_jtag_freq_set,
> + .status_get = aspeed_jtag_status_get,
> + .idle = aspeed_jtag_idle,
> + .xfer = aspeed_jtag_xfer,
> + .mode_set = aspeed_jtag_mode_set
> +};
> +
> +static int aspeed_jtag_probe(struct platform_device *pdev)
> +{
> + struct aspeed_jtag *aspeed_jtag;
> + struct device *dev;
> + struct jtag *jtag;
> + int err;
> +
> + dev = &pdev->dev;
> + if (!of_device_is_compatible(pdev->dev.of_node,
> + "aspeed,ast2500-jtag") &&
> + !of_device_is_compatible(pdev->dev.of_node,
> + "aspeed,ast2400-jtag"))
> + return -ENODEV;

Given the Aspeed device only ever probes with device tree, can you
drop these redundant checks?

> +
> + jtag = jtag_alloc(sizeof(*aspeed_jtag), &aspeed_jtag_ops);
> + if (!jtag)
> + return -ENOMEM;
> +
> + platform_set_drvdata(pdev, jtag);
> + aspeed_jtag = jtag_priv(jtag);
> + aspeed_jtag->dev = &pdev->dev;
> +
> + /* Initialize device*/
> + err = aspeed_jtag_init(pdev, aspeed_jtag);
> + if (err)
> + goto err_jtag_init;
> +
> + /* Initialize JTAG core structure*/
> + err = jtag_register(jtag);
> + if (err)
> + goto err_jtag_register;
> +
> + return 0;
> +
> +err_jtag_register:
> + aspeed_jtag_deinit(pdev, aspeed_jtag);
> +err_jtag_init:
> + jtag_free(jtag);
> + return err;
> +}
> +
> +static int aspeed_jtag_remove(struct platform_device *pdev)
> +{
> + struct jtag *jtag;
> +
> + jtag = platform_get_drvdata(pdev);
> + aspeed_jtag_deinit(pdev, jtag_priv(jtag));
> + jtag_unregister(jtag);
> + jtag_free(jtag);
> + return 0;
> +}
> +
> +static const struct of_device_id aspeed_jtag_of_match[] = {
> + { .compatible = "aspeed,ast2400-jtag", },
> + { .compatible = "aspeed,ast2500-jtag", },
> + {}
> +};
> +
> +static struct platform_driver aspeed_jtag_driver = {
> + .probe = aspeed_jtag_probe,
> + .remove = aspeed_jtag_remove,
> + .driver = {
> + .name = ASPEED_JTAG_NAME,
> + .of_match_table = aspeed_jtag_of_match,
> + },
> +};
> +module_platform_driver(aspeed_jtag_driver);
> +
> +MODULE_AUTHOR("Oleksandr Shamray <oleksandrs@xxxxxxxxxxxx>");
> +MODULE_DESCRIPTION("ASPEED JTAG driver");
> +MODULE_LICENSE("GPL v2");
> --
> 1.7.1
>

Next message: Linus Torvalds: "Re: [PATCH urgent 0/3] __restore_processor_state() fixes"
Previous message: Rafael J. Wysocki: "Re: [PATCH urgent 0/3] __restore_processor_state() fixes"
In reply to: Philippe Ombredanne: "Re: [patch v14 2/4] drivers: jtag: Add Aspeed SoC 24xx and 25xx families JTAG master driver"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]