linux/arch/arc/plat-hsdk/platform.c
Vineet Gupta 3b57533b46 ARC: [plat-hsdk] Remap CCMs super early in asm boot trampoline
ARC HSDK platform stopped booting on released v5.10-rc1, getting stuck
in startup of non master SMP cores.

This was bisected to upstream commit 7fef431be9
"(mm/page_alloc: place pages to tail in __free_pages_core())"
That commit itself is harmless, it just exposed a subtle assumption in
our platform code (hence CC'ing linux-mm just as FYI in case some other
arches / platforms trip on it).

The upstream commit is semantically disruptive as it reverses the order
of page allocations (actually it can be good test for hardware
verification to exercise different memory patterns altogether).
For ARC HSDK platform that meant a remapped memory region (pertaining to
unused Closely Coupled Memory) started getting used early for dynamice
allocations, while not effectively remapped on all the cores, triggering
memory error exception on those cores.

The fix is to move the CCM remapping from early platform code to to early core
boot code. And while it is undesirable to riddle common boot code with
platform quirks, there is no other way to do this since the faltering code
involves setting up stack itself so even function calls are not allowed at
that point.

If anyone is interested, all the gory details can be found at Link below.

Link: https://github.com/foss-for-synopsys-dwc-arc-processors/linux/issues/32
Cc: David Hildenbrand <david@redhat.com>
Cc: linux-mm@kvack.org
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2020-11-02 11:45:09 -08:00

327 lines
10 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* ARC HSDK Platform support code
*
* Copyright (C) 2017 Synopsys, Inc. (www.synopsys.com)
*/
#include <linux/init.h>
#include <linux/of_fdt.h>
#include <linux/libfdt.h>
#include <linux/smp.h>
#include <asm/arcregs.h>
#include <asm/io.h>
#include <asm/mach_desc.h>
int arc_hsdk_axi_dmac_coherent __section(".data") = 0;
#define ARC_CCM_UNUSED_ADDR 0x60000000
#define ARC_PERIPHERAL_BASE 0xf0000000
#define CREG_BASE (ARC_PERIPHERAL_BASE + 0x1000)
#define SDIO_BASE (ARC_PERIPHERAL_BASE + 0xA000)
#define SDIO_UHS_REG_EXT (SDIO_BASE + 0x108)
#define SDIO_UHS_REG_EXT_DIV_2 (2 << 30)
#define HSDK_GPIO_INTC (ARC_PERIPHERAL_BASE + 0x3000)
static void __init hsdk_enable_gpio_intc_wire(void)
{
/*
* Peripherals on CPU Card are wired to cpu intc via intermediate
* DW APB GPIO blocks (mainly for debouncing)
*
* ---------------------
* | snps,archs-intc |
* ---------------------
* |
* ----------------------
* | snps,archs-idu-intc |
* ----------------------
* | | | | |
* | [eth] [USB] [... other peripherals]
* |
* -------------------
* | snps,dw-apb-intc |
* -------------------
* | | | |
* [Bt] [HAPS] [... other peripherals]
*
* Current implementation of "irq-dw-apb-ictl" driver doesn't work well
* with stacked INTCs. In particular problem happens if its master INTC
* not yet instantiated. See discussion here -
* https://lkml.org/lkml/2015/3/4/755
*
* So setup the first gpio block as a passive pass thru and hide it from
* DT hardware topology - connect intc directly to cpu intc
* The GPIO "wire" needs to be init nevertheless (here)
*
* One side adv is that peripheral interrupt handling avoids one nested
* intc ISR hop
*
* According to HSDK User's Manual [1], "Table 2 Interrupt Mapping"
* we have the following GPIO input lines used as sources of interrupt:
* - GPIO[0] - Bluetooth interrupt of RS9113 module
* - GPIO[2] - HAPS interrupt (on HapsTrak 3 connector)
* - GPIO[3] - Audio codec (MAX9880A) interrupt
* - GPIO[8-23] - Available on Arduino and PMOD_x headers
* For now there's no use of Arduino and PMOD_x headers in Linux
* use-case so we only enable lines 0, 2 and 3.
*
* [1] https://github.com/foss-for-synopsys-dwc-arc-processors/ARC-Development-Systems-Forum/wiki/docs/ARC_HSDK_User_Guide.pdf
*/
#define GPIO_INTEN (HSDK_GPIO_INTC + 0x30)
#define GPIO_INTMASK (HSDK_GPIO_INTC + 0x34)
#define GPIO_INTTYPE_LEVEL (HSDK_GPIO_INTC + 0x38)
#define GPIO_INT_POLARITY (HSDK_GPIO_INTC + 0x3c)
#define GPIO_INT_CONNECTED_MASK 0x0d
iowrite32(0xffffffff, (void __iomem *) GPIO_INTMASK);
iowrite32(~GPIO_INT_CONNECTED_MASK, (void __iomem *) GPIO_INTMASK);
iowrite32(0x00000000, (void __iomem *) GPIO_INTTYPE_LEVEL);
iowrite32(0xffffffff, (void __iomem *) GPIO_INT_POLARITY);
iowrite32(GPIO_INT_CONNECTED_MASK, (void __iomem *) GPIO_INTEN);
}
static int __init hsdk_tweak_node_coherency(const char *path, bool coherent)
{
void *fdt = initial_boot_params;
const void *prop;
int node, ret;
bool dt_coh_set;
node = fdt_path_offset(fdt, path);
if (node < 0)
goto tweak_fail;
prop = fdt_getprop(fdt, node, "dma-coherent", &ret);
if (!prop && ret != -FDT_ERR_NOTFOUND)
goto tweak_fail;
dt_coh_set = ret != -FDT_ERR_NOTFOUND;
ret = 0;
/* need to remove "dma-coherent" property */
if (dt_coh_set && !coherent)
ret = fdt_delprop(fdt, node, "dma-coherent");
/* need to set "dma-coherent" property */
if (!dt_coh_set && coherent)
ret = fdt_setprop(fdt, node, "dma-coherent", NULL, 0);
if (ret < 0)
goto tweak_fail;
return 0;
tweak_fail:
pr_err("failed to tweak %s to %scoherent\n", path, coherent ? "" : "non");
return -EFAULT;
}
enum hsdk_axi_masters {
M_HS_CORE = 0,
M_HS_RTT,
M_AXI_TUN,
M_HDMI_VIDEO,
M_HDMI_AUDIO,
M_USB_HOST,
M_ETHERNET,
M_SDIO,
M_GPU,
M_DMAC_0,
M_DMAC_1,
M_DVFS
};
#define UPDATE_VAL 1
/*
* This is modified configuration of AXI bridge. Default settings
* are specified in "Table 111 CREG Address Decoder register reset values".
*
* AXI_M_m_SLV{0|1} - Slave Select register for master 'm'.
* Possible slaves are:
* - 0 => no slave selected
* - 1 => DDR controller port #1
* - 2 => SRAM controller
* - 3 => AXI tunnel
* - 4 => EBI controller
* - 5 => ROM controller
* - 6 => AXI2APB bridge
* - 7 => DDR controller port #2
* - 8 => DDR controller port #3
* - 9 => HS38x4 IOC
* - 10 => HS38x4 DMI
* AXI_M_m_OFFSET{0|1} - Addr Offset register for master 'm'
*
* Please read ARC HS Development IC Specification, section 17.2 for more
* information about apertures configuration.
*
* m master AXI_M_m_SLV0 AXI_M_m_SLV1 AXI_M_m_OFFSET0 AXI_M_m_OFFSET1
* 0 HS (CBU) 0x11111111 0x63111111 0xFEDCBA98 0x0E543210
* 1 HS (RTT) 0x77777777 0x77777777 0xFEDCBA98 0x76543210
* 2 AXI Tunnel 0x88888888 0x88888888 0xFEDCBA98 0x76543210
* 3 HDMI-VIDEO 0x77777777 0x77777777 0xFEDCBA98 0x76543210
* 4 HDMI-ADUIO 0x77777777 0x77777777 0xFEDCBA98 0x76543210
* 5 USB-HOST 0x77777777 0x77999999 0xFEDCBA98 0x76DCBA98
* 6 ETHERNET 0x77777777 0x77999999 0xFEDCBA98 0x76DCBA98
* 7 SDIO 0x77777777 0x77999999 0xFEDCBA98 0x76DCBA98
* 8 GPU 0x77777777 0x77777777 0xFEDCBA98 0x76543210
* 9 DMAC (port #1) 0x77777777 0x77777777 0xFEDCBA98 0x76543210
* 10 DMAC (port #2) 0x77777777 0x77777777 0xFEDCBA98 0x76543210
* 11 DVFS 0x00000000 0x60000000 0x00000000 0x00000000
*/
#define CREG_AXI_M_SLV0(m) ((void __iomem *)(CREG_BASE + 0x20 * (m)))
#define CREG_AXI_M_SLV1(m) ((void __iomem *)(CREG_BASE + 0x20 * (m) + 0x04))
#define CREG_AXI_M_OFT0(m) ((void __iomem *)(CREG_BASE + 0x20 * (m) + 0x08))
#define CREG_AXI_M_OFT1(m) ((void __iomem *)(CREG_BASE + 0x20 * (m) + 0x0C))
#define CREG_AXI_M_UPDT(m) ((void __iomem *)(CREG_BASE + 0x20 * (m) + 0x14))
#define CREG_AXI_M_HS_CORE_BOOT ((void __iomem *)(CREG_BASE + 0x010))
#define CREG_PAE ((void __iomem *)(CREG_BASE + 0x180))
#define CREG_PAE_UPDT ((void __iomem *)(CREG_BASE + 0x194))
static void __init hsdk_init_memory_bridge_axi_dmac(void)
{
bool coherent = !!arc_hsdk_axi_dmac_coherent;
u32 axi_m_slv1, axi_m_oft1;
/*
* Don't tweak memory bridge configuration if we failed to tweak DTB
* as we will end up in a inconsistent state.
*/
if (hsdk_tweak_node_coherency("/soc/dmac@80000", coherent))
return;
if (coherent) {
axi_m_slv1 = 0x77999999;
axi_m_oft1 = 0x76DCBA98;
} else {
axi_m_slv1 = 0x77777777;
axi_m_oft1 = 0x76543210;
}
writel(0x77777777, CREG_AXI_M_SLV0(M_DMAC_0));
writel(0xFEDCBA98, CREG_AXI_M_OFT0(M_DMAC_0));
writel(axi_m_slv1, CREG_AXI_M_SLV1(M_DMAC_0));
writel(axi_m_oft1, CREG_AXI_M_OFT1(M_DMAC_0));
writel(UPDATE_VAL, CREG_AXI_M_UPDT(M_DMAC_0));
writel(0x77777777, CREG_AXI_M_SLV0(M_DMAC_1));
writel(0xFEDCBA98, CREG_AXI_M_OFT0(M_DMAC_1));
writel(axi_m_slv1, CREG_AXI_M_SLV1(M_DMAC_1));
writel(axi_m_oft1, CREG_AXI_M_OFT1(M_DMAC_1));
writel(UPDATE_VAL, CREG_AXI_M_UPDT(M_DMAC_1));
}
static void __init hsdk_init_memory_bridge(void)
{
u32 reg;
/*
* M_HS_CORE has one unique register - BOOT.
* We need to clean boot mirror (BOOT[1:0]) bits in them to avoid first
* aperture to be masked by 'boot mirror'.
*/
reg = readl(CREG_AXI_M_HS_CORE_BOOT) & (~0x3);
writel(reg, CREG_AXI_M_HS_CORE_BOOT);
writel(0x11111111, CREG_AXI_M_SLV0(M_HS_CORE));
writel(0x63111111, CREG_AXI_M_SLV1(M_HS_CORE));
writel(0xFEDCBA98, CREG_AXI_M_OFT0(M_HS_CORE));
writel(0x0E543210, CREG_AXI_M_OFT1(M_HS_CORE));
writel(UPDATE_VAL, CREG_AXI_M_UPDT(M_HS_CORE));
writel(0x77777777, CREG_AXI_M_SLV0(M_HS_RTT));
writel(0x77777777, CREG_AXI_M_SLV1(M_HS_RTT));
writel(0xFEDCBA98, CREG_AXI_M_OFT0(M_HS_RTT));
writel(0x76543210, CREG_AXI_M_OFT1(M_HS_RTT));
writel(UPDATE_VAL, CREG_AXI_M_UPDT(M_HS_RTT));
writel(0x88888888, CREG_AXI_M_SLV0(M_AXI_TUN));
writel(0x88888888, CREG_AXI_M_SLV1(M_AXI_TUN));
writel(0xFEDCBA98, CREG_AXI_M_OFT0(M_AXI_TUN));
writel(0x76543210, CREG_AXI_M_OFT1(M_AXI_TUN));
writel(UPDATE_VAL, CREG_AXI_M_UPDT(M_AXI_TUN));
writel(0x77777777, CREG_AXI_M_SLV0(M_HDMI_VIDEO));
writel(0x77777777, CREG_AXI_M_SLV1(M_HDMI_VIDEO));
writel(0xFEDCBA98, CREG_AXI_M_OFT0(M_HDMI_VIDEO));
writel(0x76543210, CREG_AXI_M_OFT1(M_HDMI_VIDEO));
writel(UPDATE_VAL, CREG_AXI_M_UPDT(M_HDMI_VIDEO));
writel(0x77777777, CREG_AXI_M_SLV0(M_HDMI_AUDIO));
writel(0x77777777, CREG_AXI_M_SLV1(M_HDMI_AUDIO));
writel(0xFEDCBA98, CREG_AXI_M_OFT0(M_HDMI_AUDIO));
writel(0x76543210, CREG_AXI_M_OFT1(M_HDMI_AUDIO));
writel(UPDATE_VAL, CREG_AXI_M_UPDT(M_HDMI_AUDIO));
writel(0x77777777, CREG_AXI_M_SLV0(M_USB_HOST));
writel(0x77999999, CREG_AXI_M_SLV1(M_USB_HOST));
writel(0xFEDCBA98, CREG_AXI_M_OFT0(M_USB_HOST));
writel(0x76DCBA98, CREG_AXI_M_OFT1(M_USB_HOST));
writel(UPDATE_VAL, CREG_AXI_M_UPDT(M_USB_HOST));
writel(0x77777777, CREG_AXI_M_SLV0(M_ETHERNET));
writel(0x77999999, CREG_AXI_M_SLV1(M_ETHERNET));
writel(0xFEDCBA98, CREG_AXI_M_OFT0(M_ETHERNET));
writel(0x76DCBA98, CREG_AXI_M_OFT1(M_ETHERNET));
writel(UPDATE_VAL, CREG_AXI_M_UPDT(M_ETHERNET));
writel(0x77777777, CREG_AXI_M_SLV0(M_SDIO));
writel(0x77999999, CREG_AXI_M_SLV1(M_SDIO));
writel(0xFEDCBA98, CREG_AXI_M_OFT0(M_SDIO));
writel(0x76DCBA98, CREG_AXI_M_OFT1(M_SDIO));
writel(UPDATE_VAL, CREG_AXI_M_UPDT(M_SDIO));
writel(0x77777777, CREG_AXI_M_SLV0(M_GPU));
writel(0x77777777, CREG_AXI_M_SLV1(M_GPU));
writel(0xFEDCBA98, CREG_AXI_M_OFT0(M_GPU));
writel(0x76543210, CREG_AXI_M_OFT1(M_GPU));
writel(UPDATE_VAL, CREG_AXI_M_UPDT(M_GPU));
writel(0x00000000, CREG_AXI_M_SLV0(M_DVFS));
writel(0x60000000, CREG_AXI_M_SLV1(M_DVFS));
writel(0x00000000, CREG_AXI_M_OFT0(M_DVFS));
writel(0x00000000, CREG_AXI_M_OFT1(M_DVFS));
writel(UPDATE_VAL, CREG_AXI_M_UPDT(M_DVFS));
hsdk_init_memory_bridge_axi_dmac();
/*
* PAE remapping for DMA clients does not work due to an RTL bug, so
* CREG_PAE register must be programmed to all zeroes, otherwise it
* will cause problems with DMA to/from peripherals even if PAE40 is
* not used.
*/
writel(0x00000000, CREG_PAE);
writel(UPDATE_VAL, CREG_PAE_UPDT);
}
static void __init hsdk_init_early(void)
{
hsdk_init_memory_bridge();
/*
* Switch SDIO external ciu clock divider from default div-by-8 to
* minimum possible div-by-2.
*/
iowrite32(SDIO_UHS_REG_EXT_DIV_2, (void __iomem *) SDIO_UHS_REG_EXT);
hsdk_enable_gpio_intc_wire();
}
static const char *hsdk_compat[] __initconst = {
"snps,hsdk",
NULL,
};
MACHINE_START(SIMULATION, "hsdk")
.dt_compat = hsdk_compat,
.init_early = hsdk_init_early,
MACHINE_END