crypto: ccp - Add ACPI support

Add support for ACPI to the CCP platform driver.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

2 files changed, 93 insertions, 5 deletions

diff --git a/drivers/crypto/Kconfig b/drivers/crypto/Kconfig
index b840b79655bc..7e94413da6e3 100644
--- a/drivers/crypto/Kconfig
+++ b/drivers/crypto/Kconfig
@@ -391,7 +391,7 @@ config CRYPTO_DEV_ATMEL_SHA
 
 config CRYPTO_DEV_CCP
         bool "Support for AMD Cryptographic Coprocessor"
-        depends on ((X86 && PCI) || ARM64) && HAS_IOMEM
+        depends on ((X86 && PCI) || (ARM64 && (OF_ADDRESS || ACPI))) && HAS_IOMEM
         default n
         help
           The AMD Cryptographic Coprocessor provides hardware support
diff --git a/drivers/crypto/ccp/ccp-platform.c b/drivers/crypto/ccp/ccp-platform.c
index 20661f099198..b1c20b2b5647 100644
--- a/drivers/crypto/ccp/ccp-platform.c
+++ b/drivers/crypto/ccp/ccp-platform.c
@@ -23,9 +23,16 @@
 #include <linux/delay.h>
 #include <linux/ccp.h>
 #include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/acpi.h>
 
 #include "ccp-dev.h"
 
+struct ccp_platform {
+        int use_acpi;
+        int coherent;
+};
+
 static int ccp_get_irq(struct ccp_device *ccp)
 {
         struct device *dev = ccp->dev;
@@ -83,10 +90,64 @@ static struct resource *ccp_find_mmio_area(struct ccp_device *ccp)
         return NULL;
 }
 
+#ifdef CONFIG_ACPI
+static int ccp_acpi_support(struct ccp_device *ccp)
+{
+        struct ccp_platform *ccp_platform = ccp->dev_specific;
+        struct acpi_device *adev = ACPI_COMPANION(ccp->dev);
+        acpi_handle handle;
+        acpi_status status;
+        unsigned long long data;
+        int cca;
+
+        /* Retrieve the device cache coherency value */
+        handle = adev->handle;
+        do {
+                status = acpi_evaluate_integer(handle, "_CCA", NULL, &data);
+                if (!ACPI_FAILURE(status)) {
+                        cca = data;
+                        break;
+                }
+        } while (!ACPI_FAILURE(status));
+
+        if (ACPI_FAILURE(status)) {
+                dev_err(ccp->dev, "error obtaining acpi coherency value\n");
+                return -EINVAL;
+        }
+
+        ccp_platform->coherent = !!cca;
+
+        return 0;
+}
+#else   /* CONFIG_ACPI */
+static int ccp_acpi_support(struct ccp_device *ccp)
+{
+        return -EINVAL;
+}
+#endif
+
+#ifdef CONFIG_OF
+static int ccp_of_support(struct ccp_device *ccp)
+{
+        struct ccp_platform *ccp_platform = ccp->dev_specific;
+
+        ccp_platform->coherent = of_dma_is_coherent(ccp->dev->of_node);
+
+        return 0;
+}
+#else
+static int ccp_of_support(struct ccp_device *ccp)
+{
+        return -EINVAL;
+}
+#endif
+
 static int ccp_platform_probe(struct platform_device *pdev)
 {
         struct ccp_device *ccp;
+        struct ccp_platform *ccp_platform;
         struct device *dev = &pdev->dev;
+        struct acpi_device *adev = ACPI_COMPANION(dev);
         struct resource *ior;
         int ret;
 
@@ -95,10 +156,16 @@ static int ccp_platform_probe(struct platform_device *pdev)
         if (!ccp)
                 goto e_err;
 
-        ccp->dev_specific = NULL;
+        ccp_platform = devm_kzalloc(dev, sizeof(*ccp_platform), GFP_KERNEL);
+        if (!ccp_platform)
+                goto e_err;
+
+        ccp->dev_specific = ccp_platform;
         ccp->get_irq = ccp_get_irqs;
         ccp->free_irq = ccp_free_irqs;
 
+        ccp_platform->use_acpi = (!adev || acpi_disabled) ? 0 : 1;
+
         ior = ccp_find_mmio_area(ccp);
         ccp->io_map = devm_ioremap_resource(dev, ior);
         if (IS_ERR(ccp->io_map)) {
@@ -115,7 +182,14 @@ static int ccp_platform_probe(struct platform_device *pdev)
                 goto e_err;
         }
 
-        if (of_property_read_bool(dev->of_node, "dma-coherent"))
+        if (ccp_platform->use_acpi)
+                ret = ccp_acpi_support(ccp);
+        else
+                ret = ccp_of_support(ccp);
+        if (ret)
+                goto e_err;
+
+        if (ccp_platform->coherent)
                 ccp->axcache = CACHE_WB_NO_ALLOC;
         else
                 ccp->axcache = CACHE_NONE;
@@ -197,15 +271,29 @@ static int ccp_platform_resume(struct platform_device *pdev)
 }
 #endif
 
-static const struct of_device_id ccp_platform_ids[] = {
+#ifdef CONFIG_ACPI
+static const struct acpi_device_id ccp_acpi_match[] = {
+        { "AMDI0C00", 0 },
+        { },
+};
+#endif
+
+#ifdef CONFIG_OF
+static const struct of_device_id ccp_of_match[] = {
         { .compatible = "amd,ccp-seattle-v1a" },
         { },
 };
+#endif
 
 static struct platform_driver ccp_platform_driver = {
         .driver = {
                 .name = "AMD Cryptographic Coprocessor",
-                .of_match_table = ccp_platform_ids,
+#ifdef CONFIG_ACPI
+                .acpi_match_table = ccp_acpi_match,
+#endif
+#ifdef CONFIG_OF
+                .of_match_table = ccp_of_match,
+#endif
         },
         .probe = ccp_platform_probe,
         .remove = ccp_platform_remove,