| Message ID | 20180703060434.19293-7-vkoul@kernel.org |
|---|---|
| State | New |
| Headers | show |
| Series | None | expand |
On 03-07-18, 09:10, Timur Tabi wrote: > On 7/3/18 1:04 AM, Vinod Koul wrote: > > Add support for probing on ACPI systems, with ACPI HID QCOM8160. > > > > On ACPI systems, clocks are always enabled, the PRNG should > > already be enabled, and the register region is read-only. > > The driver only verifies that the hardware is already > > enabled never tries to disable or configure it. > > > > Signed-off-by: Timur Tabi<timur@codeaurora.org> > > [port to crypto API] > > Signed-off-by: Vinod Koul<vkoul@kernel.org> > > I've asked a colleague who still works at Qualcomm to test this code on > silicon. It looks okay, but I just want to be sure. > > > + /* > > + * ACPI systems have v2 hardware. The clocks are always enabled, > > + * the PRNG register space is read-only and the PRNG should > > + * already be enabled. > > + */ > > + if (has_acpi_companion(&pdev->dev)) { > > + val = readl(rng->base + PRNG_CONFIG); > > + if (!(val & PRNG_CONFIG_HW_ENABLE)) { > > + dev_err(&pdev->dev, "device is not enabled\n"); > > + return -ENODEV; > > + } > > I'm having second thoughts about this PRNG_CONFIG_HW_ENABLE check. The PRNG > on the QDF2400 is the same as the one on the 8996, so it should have the > same register interface. Currently, the ACPI table points to a full PRNG > register block, but I'm beginning to believe that it should instead point to > a "reduced" block that doesn't have a PRNG_CONFIG register. That was my doubt too. I will go ahead and make it skip this then... -- ~Vinod
On 7/3/2018 10:13 PM, Vinod wrote: > On 03-07-18, 11:08, Jeffrey Hugo wrote: >> On 7/3/2018 12:04 AM, Vinod Koul wrote: > >>> +#if IS_ENABLED(CONFIG_ACPI) >>> +static const struct acpi_device_id qcom_rng_acpi_match[] = { >>> + { >>> + .id = "QCOM8160", >>> + }, >>> + {} >>> +}; >>> +MODULE_DEVICE_TABLE(acpi, msm_rng_acpi_match); >> >> qcom_rng_acpi_match? >> Looks like a copy/paste issue. This causes a build failure for me. >> I'm trying to see if it works otherwise... > > Ah sorry about that, I though I had fixed it, looks like I missed to > fold the fix. > > Did it work for you? > It seems to work. Driver compiles, and loads. Still working on the verification. -- Jeffrey Hugo Qualcomm Datacenter Technologies as an affiliate of Qualcomm Technologies, Inc. Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.
diff --git a/drivers/crypto/qcom-rng.c b/drivers/crypto/qcom-rng.c index fdbbcac7bcb8..bc0131d130d6 100644 --- a/drivers/crypto/qcom-rng.c +++ b/drivers/crypto/qcom-rng.c @@ -4,6 +4,7 @@ // Based on msm-rng.c and downstream driver #include <crypto/internal/rng.h> +#include <linux/acpi.h> #include <linux/clk.h> #include <linux/crypto.h> #include <linux/module.h> @@ -154,6 +155,7 @@ static int qcom_rng_probe(struct platform_device *pdev) { struct resource *res; struct qcom_rng *rng; + u32 val; int ret; rng = devm_kzalloc(&pdev->dev, sizeof(*rng), GFP_KERNEL); @@ -168,11 +170,27 @@ static int qcom_rng_probe(struct platform_device *pdev) if (IS_ERR(rng->base)) return PTR_ERR(rng->base); - rng->clk = devm_clk_get(&pdev->dev, "core"); - if (IS_ERR(rng->clk)) - return PTR_ERR(rng->clk); - rng->skip_init = (unsigned long)of_device_get_match_data(&pdev->dev); + /* + * ACPI systems have v2 hardware. The clocks are always enabled, + * the PRNG register space is read-only and the PRNG should + * already be enabled. + */ + if (has_acpi_companion(&pdev->dev)) { + val = readl(rng->base + PRNG_CONFIG); + if (!(val & PRNG_CONFIG_HW_ENABLE)) { + dev_err(&pdev->dev, "device is not enabled\n"); + return -ENODEV; + } + rng->skip_init = 1; + } else { + rng->clk = devm_clk_get(&pdev->dev, "core"); + if (IS_ERR(rng->clk)) + return PTR_ERR(rng->clk); + + rng->skip_init = + (unsigned long)of_device_get_match_data(&pdev->dev); + } qcom_rng_dev = rng; ret = crypto_register_rng(&qcom_rng_alg); @@ -193,6 +211,16 @@ static int qcom_rng_remove(struct platform_device *pdev) return 0; } +#if IS_ENABLED(CONFIG_ACPI) +static const struct acpi_device_id qcom_rng_acpi_match[] = { + { + .id = "QCOM8160", + }, + {} +}; +MODULE_DEVICE_TABLE(acpi, msm_rng_acpi_match); +#endif + static const struct of_device_id qcom_rng_of_match[] = { { .compatible = "qcom,prng", .data = (void *)0}, { .compatible = "qcom,prng-ee", .data = (void *)1}, @@ -206,6 +234,7 @@ static struct platform_driver qcom_rng_driver = { .driver = { .name = KBUILD_MODNAME, .of_match_table = of_match_ptr(qcom_rng_of_match), + .acpi_match_table = ACPI_PTR(qcom_rng_acpi_match), } }; module_platform_driver(qcom_rng_driver);