From patchwork Fri Dec 15 11:47:46 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thangaraj Samynathan X-Patchwork-Id: 13494359 Received: from esa.microchip.iphmx.com (esa.microchip.iphmx.com [68.232.153.233]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1CB57250F9; Fri, 15 Dec 2023 11:50:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=microchip.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=microchip.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=microchip.com header.i=@microchip.com header.b="F16odioc" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=microchip.com; i=@microchip.com; q=dns/txt; s=mchp; t=1702641027; x=1734177027; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=pCX1ECWz6AH7SgM0njcfU2IlPtMHstb/aOqlR8RvaxI=; b=F16odiocSUAwHiJD7amPueu/uvI3AHNopX/hd9u7hDZkxnaiLr3XG48C 2E9ZD8UcGiSfdNJMYDnzIESZ37TxG1LELj1JCMSG1PRrLPcqOwu2/9rrT aI4/HYYe1OdENK2YUfKe5H138KZ2Ct9PebEUZWXZSc6OPSQSiQWiHHtAs LYB7xGN5Gz0DRfhLrmUwm8ZIoNoYJCtunK8sQgEEW2KMzXnq0220U3MkD v0LVHvrxNOauqLlvy5hclw1mc6gjgRPjGd8m2P94Kw9bNrAnPKwMLkC46 ZRuBK3rQYAdhF9KI0dSH4Wntkk+9cjqOAxym4nuApEMFdSRZUnLT6T9uW A==; X-CSE-ConnectionGUID: LGva2yzVSgmRfFnu4BtIaw== X-CSE-MsgGUID: 9y+XknkMQqqkC0QqYskCKg== X-ThreatScanner-Verdict: Negative X-IronPort-AV: E=Sophos;i="6.04,278,1695711600"; d="scan'208";a="14317229" X-Amp-Result: SKIPPED(no attachment in message) Received: from unknown (HELO email.microchip.com) ([170.129.1.10]) by esa1.microchip.iphmx.com with ESMTP/TLS/ECDHE-RSA-AES128-GCM-SHA256; 15 Dec 2023 04:50:20 -0700 Received: from chn-vm-ex03.mchp-main.com (10.10.85.151) by chn-vm-ex03.mchp-main.com (10.10.85.151) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.35; Fri, 15 Dec 2023 04:50:04 -0700 Received: from che-dk-ungapp03lx.microchip.com (10.10.85.11) by chn-vm-ex03.mchp-main.com (10.10.85.151) with Microsoft SMTP Server id 15.1.2507.35 via Frontend Transport; Fri, 15 Dec 2023 04:50:01 -0700 From: Thangaraj Samynathan To: CC: , , , , , , Subject: [PATCH SPI for-next 1/3] spi: mchp-pci1xxxx: Add support for DMA in SPI Date: Fri, 15 Dec 2023 17:17:46 +0530 Message-ID: <20231215114748.152319-2-thangaraj.s@microchip.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20231215114748.152319-1-thangaraj.s@microchip.com> References: <20231215114748.152319-1-thangaraj.s@microchip.com> Precedence: bulk X-Mailing-List: linux-spi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 In PCI1xxxx C0, support for DMA in PCIe endpoint is added to enhance the SPI performance. With this support, the performance is improved from 6Mbps to 17Mbps with 20Mhz clock. - DMA Supports two Channels, 0 and 1 - SPI Instance 0 uses chan 0 and SPI Instance 1 uses chan 1 - DMA can be used only if SPI is mapped to PF0 in the multi function endpoint and the MSI interrupt is supported - MSI interrupt of one of the SPI instance is assigned to the DMA and both channels 0 and 1 share the same irq, the MSI address and MSI Data of the irq is obtained and stored in DMA registers to generate interrupt Signed-off-by: Thangaraj Samynathan --- drivers/spi/spi-pci1xxxx.c | 135 +++++++++++++++++++++++++++++++++++++ 1 file changed, 135 insertions(+) diff --git a/drivers/spi/spi-pci1xxxx.c b/drivers/spi/spi-pci1xxxx.c index 5b2d3e4e21b7..95b1255e62cd 100644 --- a/drivers/spi/spi-pci1xxxx.c +++ b/drivers/spi/spi-pci1xxxx.c @@ -5,7 +5,12 @@ // Kumaravel Thiagarajan +#include +#include +#include #include +#include +#include #include #include #include @@ -32,8 +37,33 @@ #define SPI_MST_CTL_MODE_SEL (BIT(2)) #define SPI_MST_CTL_GO (BIT(0)) +#define SPI_SYSTEM_ADDR_BASE (0x2000) #define SPI_MST1_ADDR_BASE (0x800) +#define DEV_REV_REG (SPI_SYSTEM_ADDR_BASE + 0x00) +#define SPI_SYSLOCK_REG (SPI_SYSTEM_ADDR_BASE + 0xA0) +#define SPI_CONFIG_PERI_ENABLE_REG (SPI_SYSTEM_ADDR_BASE + 0x108) + +#define SPI_PERI_ENBLE_PF_MASK (GENMASK(17, 16)) +#define DEV_REV_MASK (GENMASK(7, 0)) + +#define SPI_SYSLOCK BIT(4) + +/* DMA Related Registers */ +#define SPI_DMA_ADDR_BASE (0x1000) +#define SPI_DMA_GLOBAL_WR_ENGINE_EN (SPI_DMA_ADDR_BASE + 0x0C) +#define SPI_DMA_GLOBAL_RD_ENGINE_EN (SPI_DMA_ADDR_BASE + 0x2C) +#define SPI_DMA_INTR_IMWR_WDONE_LOW (SPI_DMA_ADDR_BASE + 0x60) +#define SPI_DMA_INTR_IMWR_WDONE_HIGH (SPI_DMA_ADDR_BASE + 0x64) +#define SPI_DMA_INTR_IMWR_WABORT_LOW (SPI_DMA_ADDR_BASE + 0x68) +#define SPI_DMA_INTR_IMWR_WABORT_HIGH (SPI_DMA_ADDR_BASE + 0x6C) +#define SPI_DMA_INTR_WR_IMWR_DATA (SPI_DMA_ADDR_BASE + 0x70) +#define SPI_DMA_INTR_IMWR_RDONE_LOW (SPI_DMA_ADDR_BASE + 0xCC) +#define SPI_DMA_INTR_IMWR_RDONE_HIGH (SPI_DMA_ADDR_BASE + 0xD0) +#define SPI_DMA_INTR_IMWR_RABORT_LOW (SPI_DMA_ADDR_BASE + 0xD4) +#define SPI_DMA_INTR_IMWR_RABORT_HIGH (SPI_DMA_ADDR_BASE + 0xD8) +#define SPI_DMA_INTR_RD_IMWR_DATA (SPI_DMA_ADDR_BASE + 0xDC) + /* x refers to SPI Host Controller HW instance id in the below macros - 0 or 1 */ #define SPI_MST_CMD_BUF_OFFSET(x) (((x) * SPI_MST1_ADDR_BASE) + 0x00) @@ -50,6 +80,8 @@ #define SPI_MAX_DATA_LEN 320 #define PCI1XXXX_SPI_TIMEOUT (msecs_to_jiffies(100)) +#define SYSLOCK_RETRY_CNT (1000) +#define SPI_DMA_ENGINE_EN (0x1) #define SPI_INTR BIT(8) #define SPI_FORCE_CE BIT(4) @@ -76,7 +108,10 @@ struct pci1xxxx_spi_internal { struct pci1xxxx_spi { struct pci_dev *dev; u8 total_hw_instances; + u8 dev_rev; void __iomem *reg_base; + void __iomem *dma_offset_bar; + bool can_dma; struct pci1xxxx_spi_internal *spi_int[] __counted_by(total_hw_instances); }; @@ -106,6 +141,102 @@ static const struct pci_device_id pci1xxxx_spi_pci_id_table[] = { MODULE_DEVICE_TABLE(pci, pci1xxxx_spi_pci_id_table); +static int pci1xxxx_set_sys_lock(struct pci1xxxx_spi *par) +{ + writel(SPI_SYSLOCK, par->reg_base + SPI_SYSLOCK_REG); + return readl(par->reg_base + SPI_SYSLOCK_REG); +} + +static int pci1xxxx_acquire_sys_lock(struct pci1xxxx_spi *par) +{ + u32 regval; + + return readx_poll_timeout(pci1xxxx_set_sys_lock, par, regval, + (regval & SPI_SYSLOCK), 100, + SYSLOCK_RETRY_CNT * 100); +} + +static void pci1xxxx_release_sys_lock(struct pci1xxxx_spi *par) +{ + writel(0x0, par->reg_base + SPI_SYSLOCK_REG); +} + +static int pci1xxxx_check_spi_can_dma(struct pci1xxxx_spi *spi_bus, int irq) +{ + struct pci_dev *pdev = spi_bus->dev; + u32 pf_num; + u32 regval; + int ret; + + /* + * DEV REV Registers is a system register, HW Syslock bit + * should be acquired before accessing the register + */ + ret = pci1xxxx_acquire_sys_lock(spi_bus); + if (ret) + return ret; + + regval = readl(spi_bus->reg_base + DEV_REV_REG); + spi_bus->dev_rev = regval & DEV_REV_MASK; + if (spi_bus->dev_rev >= 0xC0) { + regval = readl(spi_bus->reg_base + + SPI_CONFIG_PERI_ENABLE_REG); + pf_num = regval & SPI_PERI_ENBLE_PF_MASK; + } + + pci1xxxx_release_sys_lock(spi_bus); + + /* + * DMA is supported only from C0 and SPI can use DMA only if + * it is mapped to PF0 + */ + if (spi_bus->dev_rev < 0xC0 || pf_num) + return -EOPNOTSUPP; + + /* + * DMA Supported only with MSI Interrupts + * One of the SPI instance's MSI vector address and data + * is used for DMA Interrupt + */ + if (!irq_get_msi_desc(irq)) + return -EOPNOTSUPP; + + spi_bus->dma_offset_bar = pcim_iomap(pdev, 2, pci_resource_len(pdev, 2)); + if (!spi_bus->dma_offset_bar) + return -EOPNOTSUPP; + + if (dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64))) + return -EOPNOTSUPP; + + return 0; +} + +static int pci1xxxx_spi_dma_init(struct pci1xxxx_spi *spi_bus, int irq) +{ + struct msi_msg msi; + int ret; + + ret = pci1xxxx_check_spi_can_dma(spi_bus, irq); + if (ret) + return ret; + + get_cached_msi_msg(irq, &msi); + writel(SPI_DMA_ENGINE_EN, spi_bus->dma_offset_bar + SPI_DMA_GLOBAL_WR_ENGINE_EN); + writel(SPI_DMA_ENGINE_EN, spi_bus->dma_offset_bar + SPI_DMA_GLOBAL_RD_ENGINE_EN); + writel(msi.address_hi, spi_bus->dma_offset_bar + SPI_DMA_INTR_IMWR_WDONE_HIGH); + writel(msi.address_hi, spi_bus->dma_offset_bar + SPI_DMA_INTR_IMWR_WABORT_HIGH); + writel(msi.address_hi, spi_bus->dma_offset_bar + SPI_DMA_INTR_IMWR_RDONE_HIGH); + writel(msi.address_hi, spi_bus->dma_offset_bar + SPI_DMA_INTR_IMWR_RABORT_HIGH); + writel(msi.address_lo, spi_bus->dma_offset_bar + SPI_DMA_INTR_IMWR_WDONE_LOW); + writel(msi.address_lo, spi_bus->dma_offset_bar + SPI_DMA_INTR_IMWR_WABORT_LOW); + writel(msi.address_lo, spi_bus->dma_offset_bar + SPI_DMA_INTR_IMWR_RDONE_LOW); + writel(msi.address_lo, spi_bus->dma_offset_bar + SPI_DMA_INTR_IMWR_RABORT_LOW); + writel(msi.data, spi_bus->dma_offset_bar + SPI_DMA_INTR_WR_IMWR_DATA); + writel(msi.data, spi_bus->dma_offset_bar + SPI_DMA_INTR_RD_IMWR_DATA); + spi_bus->can_dma = true; + return 0; +} + static void pci1xxxx_spi_set_cs(struct spi_device *spi, bool enable) { struct pci1xxxx_spi_internal *p = spi_controller_get_devdata(spi->controller); @@ -324,6 +455,10 @@ static int pci1xxxx_spi_probe(struct pci_dev *pdev, const struct pci_device_id * goto error; } + ret = pci1xxxx_spi_dma_init(spi_bus, spi_sub_ptr->irq); + if (ret && ret != -EOPNOTSUPP) + return ret; + /* This register is only applicable for 1st instance */ regval = readl(spi_bus->reg_base + SPI_PCI_CTRL_REG_OFFSET(0)); if (!only_sec_inst)