From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thierry Reding Subject: [PATCH v5 09/16] PCI: tegra: set up PADS_REFCLK_CFG1 Date: Thu, 25 Jul 2013 10:53:23 -0700 Message-ID: <1374774810-18459-10-git-send-email-thierry.reding@gmail.com> References: <1374774810-18459-1-git-send-email-thierry.reding@gmail.com> Return-path: In-Reply-To: <1374774810-18459-1-git-send-email-thierry.reding@gmail.com> Sender: linux-kernel-owner@vger.kernel.org To: Bjorn Helgaas , Stephen Warren Cc: Russell King , Jason Cooper , Thomas Petazzoni , Jay Agarwal , linux-pci@vger.kernel.org, linux-tegra@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org List-Id: linux-tegra@vger.kernel.org From: Stephen Warren The registers PADS_REFCLK_CFG are an array of 16-bit data, one entry per PCIe root port. For Tegra30, we therefore need to write a 3rd entry in this array. Doing so mays the mini-PCIe slot on Beaver operate correctly. While we're at it, add some #defines to partially document the fields within these 16-bit values. Signed-off-by: Stephen Warren Signed-off-by: Thierry Reding --- drivers/pci/host/pci-tegra.c | 29 ++++++++++++++++++++++++----- 1 file changed, 24 insertions(+), 5 deletions(-) diff --git a/drivers/pci/host/pci-tegra.c b/drivers/pci/host/pci-tegra.c index 5347d7d..0c84c67 100644 --- a/drivers/pci/host/pci-tegra.c +++ b/drivers/pci/host/pci-tegra.c @@ -196,6 +196,25 @@ #define PADS_REFCLK_CFG0 0x000000C8 #define PADS_REFCLK_CFG1 0x000000CC +/* + * Fields in PADS_REFCLK_CFG*. Those registers form an array of 16-bit + * entries, one entry per PCIe port. These field definitions and desired + * values aren't in the TRM, but do come from NVIDIA. + */ +#define PADS_REFCLK_CFG_TERM_SHIFT 2 /* 6:2 */ +#define PADS_REFCLK_CFG_E_TERM_SHIFT 7 +#define PADS_REFCLK_CFG_PREDI_SHIFT 8 /* 11:8 */ +#define PADS_REFCLK_CFG_DRVI_SHIFT 12 /* 15:12 */ + +/* Default value provided by HW engineering is 0xfa5c */ +#define PADS_REFCLK_CFG_VALUE \ + ( \ + (0x17 << PADS_REFCLK_CFG_TERM_SHIFT) | \ + (0 << PADS_REFCLK_CFG_E_TERM_SHIFT) | \ + (0xa << PADS_REFCLK_CFG_PREDI_SHIFT) | \ + (0xf << PADS_REFCLK_CFG_DRVI_SHIFT) \ + ) + struct tegra_msi { struct msi_chip chip; DECLARE_BITMAP(used, INT_PCI_MSI_NR); @@ -809,11 +828,11 @@ static int tegra_pcie_enable_controller(struct tegra_pcie *pcie) value |= PADS_PLL_CTL_RST_B4SM; pads_writel(pcie, value, soc->pads_pll_ctl); - /* - * Hack, set the clock voltage to the DEFAULT provided by hw folks. - * This doesn't exist in the documentation. - */ - pads_writel(pcie, 0xfa5cfa5c, PADS_REFCLK_CFG0); + /* Configure the reference clock driver */ + value = PADS_REFCLK_CFG_VALUE | (PADS_REFCLK_CFG_VALUE << 16); + pads_writel(pcie, value, PADS_REFCLK_CFG0); + if (soc->num_ports > 2) + pads_writel(pcie, PADS_REFCLK_CFG_VALUE, PADS_REFCLK_CFG1); /* wait for the PLL to lock */ timeout = 300; -- 1.8.1.5