From 592d8c8ccef6c8bdbe6d03fd01fd5baea921dc83 Mon Sep 17 00:00:00 2001 From: Mihail Atanassov Date: Mon, 23 Jan 2017 13:46:41 +0000 Subject: [PATCH] drm: mali-dp: Check hw version matches device-tree Refuse to bind if the device-tree compatible string lists a different hardware version. Reviewed-by: Brian Starkey Signed-off-by: Mihail Atanassov Signed-off-by: Liviu Dudau --- drivers/gpu/drm/arm/malidp_drv.c | 52 +++++++++++++++++++++++++++++++ drivers/gpu/drm/arm/malidp_regs.h | 2 ++ 2 files changed, 54 insertions(+) diff --git a/drivers/gpu/drm/arm/malidp_drv.c b/drivers/gpu/drm/arm/malidp_drv.c index 080f7631c672..6e59b3effb97 100644 --- a/drivers/gpu/drm/arm/malidp_drv.c +++ b/drivers/gpu/drm/arm/malidp_drv.c @@ -255,6 +255,46 @@ static const struct of_device_id malidp_drm_of_match[] = { }; MODULE_DEVICE_TABLE(of, malidp_drm_of_match); +static bool malidp_is_compatible_hw_id(struct malidp_hw_device *hwdev, + const struct of_device_id *dev_id) +{ + u32 core_id; + const char *compatstr_dp500 = "arm,mali-dp500"; + bool is_dp500; + bool dt_is_dp500; + + /* + * The DP500 CORE_ID register is in a different location, so check it + * first. If the product id field matches, then this is DP500, otherwise + * check the DP550/650 CORE_ID register. + */ + core_id = malidp_hw_read(hwdev, MALIDP500_DC_BASE + MALIDP_DE_CORE_ID); + /* Offset 0x18 will never read 0x500 on products other than DP500. */ + is_dp500 = (MALIDP_PRODUCT_ID(core_id) == 0x500); + dt_is_dp500 = strnstr(dev_id->compatible, compatstr_dp500, + sizeof(dev_id->compatible)) != NULL; + if (is_dp500 != dt_is_dp500) { + DRM_ERROR("Device-tree expects %s, but hardware %s DP500.\n", + dev_id->compatible, is_dp500 ? "is" : "is not"); + return false; + } else if (!dt_is_dp500) { + u16 product_id; + char buf[32]; + + core_id = malidp_hw_read(hwdev, + MALIDP550_DC_BASE + MALIDP_DE_CORE_ID); + product_id = MALIDP_PRODUCT_ID(core_id); + snprintf(buf, sizeof(buf), "arm,mali-dp%X", product_id); + if (!strnstr(dev_id->compatible, buf, + sizeof(dev_id->compatible))) { + DRM_ERROR("Device-tree expects %s, but hardware is DP%03X.\n", + dev_id->compatible, product_id); + return false; + } + } + return true; +} + #define MAX_OUTPUT_CHANNELS 3 static int malidp_bind(struct device *dev) @@ -265,6 +305,7 @@ static int malidp_bind(struct device *dev) struct malidp_drm *malidp; struct malidp_hw_device *hwdev; struct platform_device *pdev = to_platform_device(dev); + struct of_device_id const *dev_id; /* number of lines for the R, G and B output */ u8 output_width[MAX_OUTPUT_CHANNELS]; int ret = 0, i; @@ -327,6 +368,17 @@ static int malidp_bind(struct device *dev) clk_prepare_enable(hwdev->aclk); clk_prepare_enable(hwdev->mclk); + dev_id = of_match_device(malidp_drm_of_match, dev); + if (!dev_id) { + ret = -EINVAL; + goto query_hw_fail; + } + + if (!malidp_is_compatible_hw_id(hwdev, dev_id)) { + ret = -EINVAL; + goto query_hw_fail; + } + ret = hwdev->query_hw(hwdev); if (ret) { DRM_ERROR("Invalid HW configuration\n"); diff --git a/drivers/gpu/drm/arm/malidp_regs.h b/drivers/gpu/drm/arm/malidp_regs.h index 73fecb38f955..7a89997dd134 100644 --- a/drivers/gpu/drm/arm/malidp_regs.h +++ b/drivers/gpu/drm/arm/malidp_regs.h @@ -92,6 +92,8 @@ #define MALIDP_DE_H_ACTIVE(x) (((x) & 0x1fff) << 0) #define MALIDP_DE_V_ACTIVE(x) (((x) & 0x1fff) << 16) +#define MALIDP_PRODUCT_ID(__core_id) ((u32)(__core_id) >> 16) + /* register offsets and bits specific to DP500 */ #define MALIDP500_DC_BASE 0x00000 #define MALIDP500_DC_CONTROL 0x0000c -- 2.20.1