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PCI: tegra: set up PADS_REFCLK_CFG1

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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 makes 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 <swarren@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
This commit is contained in:
Stephen Warren 2013-08-09 16:49:25 +02:00
parent 94716cddbe
commit b02b07adb1
1 changed files with 24 additions and 5 deletions
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29
drivers/pci/host/pci-tegra.c
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@ -195,6 +195,25 @@
#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);
@ -808,11 +827,11 @@ 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;